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Nathan Goodyear

Metabolite Profiling Identifies a Key Role for Glycine in Rapid Cancer Cell Proliferation - 0 views

www.sciencemag.org/...1040

cancer glycine

shared by Nathan Goodyear on 19 Jun 13 - No Cached
  • Nathan Goodyear on 19 Jun 13
     
    Glycine used by cancer cells as source of energy.  This occurs through substrate phosphorylation.  This is the same reason that glutamine should be avoided in those individuals suffering from cancer.
Nathan Goodyear

Metabolite profiles and the risk of developing diabetes : Nature Medicine : Nature Publ... - 0 views

www.nature.com/...nm.2307.html

diabetes metabolism branch chain overload hypothesis branched chain amino acids amino acids protein isoleucine leucine valine tyrosine phenylalanine

shared by Nathan Goodyear on 21 Oct 13 - No Cached
  • Nathan Goodyear on 21 Oct 13
     
    High amino acid intake associated with 5 fold higher risk of Diabetes.  The risk required 3 out of 5 amino acids isoleucine, leucine, valine, tyrosine, and phenylalanine.
Nathan Goodyear

Estrogen metabolite ratio: Is the 2-hydroxyestrone to 16α-hydroxyestrone rati... - 0 views

www.ncbi.nlm.nih.gov/...PMC3039007

breast cancer 2-OH-estrone 2-OH 4-OH 2:16alpha-OHE1 2:16 estrogen metabolism

shared by Nathan Goodyear on 02 Jan 13 - No Cached
  • A recent study of nine patients concluded that the urinary EMR is a good approximation for breast tissue EMR
  • A single study in young women not using oral contraceptives found fair correlation coefficients between urinary and plasma EMR
  • All of nine properly designed epidemiological studies (six prospective case-control studies and three retrospective studies) failed to show a significant relationship between urinary or circulating EMR (2OHE1/16αOHE1) and breast cancer risk
  • ...2 more annotations...
  • premenopausal studies on urinary EMR have suggested a potentially weak inverse relationship, associations were not significantly different compared with postmenopausal or overall combined studies
  • at present, there is no evidence that the EMR can predict breast cancer risk
  • Nathan Goodyear on 02 Jan 13
     
    The 2:16 OH estrone pathway is shown to not be predictive biomarker for breast cancer.
Nathan Goodyear

Branched Chain Amino Acid Supplementation for Patients with Cirrhosis | Clinical Correl... - 0 views

www.clinicalcorrelations.org/?p=3544

BCCA branched chain amino acids liver cirrhosis hepatitis amino acids

shared by Nathan Goodyear on 05 Oct 15 - No Cached
  • low level of BCAAs in patients with cirrhosis is hypothesized to be one of multiple factors responsible for development of hepatic encephalopathy
  • supplementation of BCAAs is thought to facilitate ammonia detoxification by supporting synthesis of glutamine, one of the non-branched chain amino acids, in skeletal muscle and in the brain as well as diminishing the influx of AAAs across the blood-brain barrier
  • oral BCAA supplementation is more useful in chronic encephalopathic patients than is parenteral BCAA supplementation in patients with acute encephalopathy
  • ...35 more annotations...
  • malnutrition progressing to cachexia is another common manifestation of cirrhosis
  • Malnutrition can be mitigated with BCAA supplementation
  • Studies show that administration of amino acid formulas enriched with BCAAs can reduce protein loss, support protein synthesis, and improve nutritional status of patients with chronic liver disease
  • Leucine has been shown to be the most effective of the BCAAs because it acts via multiple pathways to stimulate protein synthesis
  • BCAAs metabolites inhibit proteolysis
  • Patients with cirrhosis have both insulin deficiency and insulin resistance
  • BCAAs (particularly leucine) help to reverse the catabolic, hyperglucagonemic state of cirrhosis both by stimulating insulin release from the pancreatic β cells and by decreasing insulin resistance allowing for better glucose utilization
  • Coadministration of BCAAs and glucose has been found to be particularly useful
  • BCAA supplementation improves protein-energy malnutrition by improving utilization of glucose, thereby diminishing the drive for proteolysis, inhibiting protein breakdown, and stimulating protein synthesis
  • Cirrhotic patients have impaired immune defense, characterized by defective phagocytic activity and impaired intracellular killing activity
  • another effect of BCAA supplementation is improvement of phagocytic function of neutrophils and possibly improvement in natural killer T (NKT) cell lymphocyte activity
  • BCAA supplementation may reduce the risk of infection in patients with advanced cirrhosis not only through improvement in protein-energy malnutrition but also by directly improving the function of the immune cells themselves
  • BCAA administration has also been shown to have a positive effect on liver regeneration
  • A proposed mechanism for improved liver regeneration is the stimulatory effect of BCAAs (particularly leucine) on the secretion of hepatocyte growth factor by hepatic stellate cells
  • BCAAs activate rapamycin signaling pathways which promotes albumin synthesis in the liver as well as protein and glycogen synthesis in muscle tissue
  • Chemical improvement with BCAA treatment is demonstrated by recovery of serum albumin and lowering of serum bilirubin levels
  • long-term oral BCAA supplementation was useful in staving off malnutrition and improving survival by preventing end-stage fatal complications of cirrhosis such as hepatic failure and gastrointestinal bleeding
  • The incidence of death by any cause, development of liver cancer, rupture of esophageal varices, or progression to hepatic failure was decreased in the group that received BCAA supplementation
  • Patients receiving BCAA supplementation also have a lower average hospital admission rate, better nutritional status, and better liver function tests
  • patients taking BCAA supplementation report improved quality of life
  • BCAAs have been shown to mitigate hepatic encephalopathy, cachexia, and infection rates, complications associated with the progression of hepatic cirrhosis
  • BCAAs make up 20-25% of the protein content of most foods
  • Highest levels are found in casein whey protein of dairy products and vegetables, such as corn and mushrooms. Other sources include egg albumin, beans, peanuts and brown rice bran
  • In addition to BCAAs from diet, oral supplements of BCAAs can be used
  • Oral supplementation tends to provide a better hepatic supply of BCAAs for patients able to tolerate PO nutrition as compared with IV supplementation, especially when treating symptoms of hepatic encephalopathy
  • Coadministration of BCAAs with carnitine and zinc has also been shown to increase ammonia metabolism further reducing the encephalopathic symptoms
  • Cirrhotic patients benefit from eating frequent, small meals that prevent long fasts which place the patient in a catabolic state
  • the best time for BCAA supplementation is at bedtime to improve the catabolic state during starvation in early morning fasting
  • A late night nutritional snack reduces symptoms of weakness and fatigability, lowers postprandial hyperglycemia, increases skeletal muscle mass,[25] improves nitrogen balance, and increases serum albumin levels.[26] Nocturnal BCAAs even improve serum albumin in cirrhotic patients who show no improvement with daytime BCAAs
  • Protein-energy malnutrition (PEM), with low serum albumin and low muscle mass, occurs in 65-90% of cases of advanced cirrhosis
  • hyperglucagonemia results in a catabolic state eventually producing anorexia and cachexia
  • BCAAs are further depleted from the circulation due to increased uptake by skeletal muscles that use the BCAAs in the synthesis of glutamine, which is produced in order to clear the ammonia that is not cleared by the failing liver
  • patients with chronic liver disease, particularly cirrhosis, routinely have decreased BCAAs and increased aromatic amino acids (AAAs) in their circulation
  • Maintaining a higher serum albumin in patients with cirrhosis is associated with decreased mortality and improved quality of life
  • the serum BCAA concentration is strongly correlated with the serum albumin level
  • Nathan Goodyear on 05 Oct 15
     
    great review of cirrhosis and BCCA supplementation.
Nathan Goodyear

Plant polyphenols as dietary antioxidants in human health and disease - 0 views

www.ncbi.nlm.nih.gov/...PMC2835915

polyphenols antioxidants nutrition

shared by Nathan Goodyear on 29 Sep 15 - No Cached
  • Polyphenols are naturally occurring compounds found largely in the fruits, vegetables, cereals and beverages
  • Polyphenols are secondary metabolites of plants
  • Nathan Goodyear on 29 Sep 15
     
    polyphenols
Nathan Goodyear

Attention-Deficit/Hyperactivity Disorder and Urinary Metabolites of Organophosphate Pes... - 0 views

pediatrics.aappublications.org/...e1270

ADHD pesticide exposure Organophosphates

shared by Nathan Goodyear on 21 Mar 11 - No Cached
  • Nathan Goodyear on 21 Mar 11
     
    ADHD and pesticide exposure
Nathan Goodyear

Do urinary oestrogen metabolites predict breast ca... [Br J Cancer. 1998] - PubMed result - 0 views

www.ncbi.nlm.nih.gov/...9820189

estrogen metabolism breast cancer 2:16alpha-OHE1

shared by Nathan Goodyear on 23 Aug 11 - No Cached
  • post-menopausal (but not premenopausal) women at baseline who went on to develop breast cancer showed about a 15% lower 2:16alpha-OHE1 ratio than matched control subjects
  • Nathan Goodyear on 23 Aug 11
     
    can the pathway of estrogen metabolism help to predict postmenopausal breast cancer?  according to this study, yes.
Nathan Goodyear

Deiodinases - National Academy of HypothyroidismNational Academy of Hypothyroidism - 0 views

www.nahypothyroidism.org/deiodinases

Thyroid hormone hormones physiology T4 T3 rT3 reverse T3 metabolites deiodinase

shared by Nathan Goodyear on 23 Nov 14 - No Cached
  • Nathan Goodyear on 23 Nov 14
     
    Great review of thyroid metabolism.
Nathan Goodyear

European Journal of Clinical Nutrition - Effect of maternal n-3 long-chain polyunsatura... - 0 views

www.nature.com/...ejcn2014158a.html

nutrition n-3 omega 3 omega-3 fish oil pregnancy childhood obesity

shared by Nathan Goodyear on 22 Dec 14 - No Cached
  • It is estimated that approximately 30% of children and adolescents in the United States and about 15–30% of those in Europe can be classified as overweight or obese
  • An increasing body of evidence now suggests that the nutritional environment encountered in utero and the early postnatal life may elicit permanent alterations in adipose tissue structure or function and, thereby, programme the individual’s propensity to later obesity
  • The composition of fatty acids in the Western diets has shifted toward an increasing dominance of n-6 relative to n-3 LCPUFAs over the past decades.9,10 This shift is also reflected in the fatty acid composition of breast milk
  • ...8 more annotations...
  • Evidence from animal studies suggests that the n-6 LCPUFA arachidonic acid promotes adipose tissue deposition, whereas the n-3 LCPUFAs eicosapentaenoic acid and docosahexaenoic acid seem to exert an opposite effect
  • Overall, no effect of supplementation was found on BMI in preschool (<5 years) and school-aged (6–12 years) children
  • increased adiposity, once established in childhood, tends to track into adulthood
  • Many studies have shown that even children <2 years with a high BMI are at increased risk of developing obesity later in life
  • The acquisition of fat cells early in life appears to be an irreversible process
  • Evidence from cell culture and animal studies suggests that early exposure to n-3 LCPUFAs has the potential to limit adipose tissue deposition mainly by attenuating the production of the arachidonic acid metabolite prostacyclin, which has been shown to enhance adipogenesis
  • In conclusion, there is currently no evidence to support that maternal n-3 LCPUFA supplementation during pregnancy and/or lactation exerts a favourable programming effect on adiposity status in childhood
  • our systematic review highlights that most of the trials reviewed were prone to methodological limitations
  • Nathan Goodyear on 22 Dec 14
     
    Literature review finds limited data (9 studies, only 6 RCTs) of omega-3 during pregnancy.  No data was found that supported reduced obesity in children by mothers taking n-3 during pregnancy.  No harm was found either.  Data was sparse.   Take home: not enough data, no harm to pregnancy, children, thus if indications are present for mother, then recommend n-3.  At this point not studies have pointed to reduced obesity in children.
Nathan Goodyear

http://press.endocrine.org/doi/pdf/10.1210/jc.2014-1872 - 0 views

press.endocrine.org/...jc.2014-1872

low T Testosterone treatment therapy diabetes obesity men male hormone hormones

shared by Nathan Goodyear on 29 Jul 14 - No Cached
  • Nathan Goodyear on 29 Jul 14
     
    New study finds Testosterone therapy provides less than statistical significant improvement in constitutional/sexual symptoms, in obese men with type II diabetes with symptoms classified as mild-moderate with modest reductions in Total Testosterone.  This study highlights that low Testosterone is a biomarker of poor health and multiple comorbidities and that simply adding in Testosterone therapy will not cure all male woes.  The authors did state that ED and low T are separate issues and I will differ with them on this--they are in fact link.  This association may vary between individuals, but to flatly state they are completely separate issues is devoid of the fact that testosterone has been shown to reduce inflammatory cytokines and improve PDE5 therapy.  
Nathan Goodyear

Urinary Phthalate Metabolites Are Associated With Decreased Serum Testosterone in Men, ... - 0 views

press.endocrine.org/...jc.2014-2555

phthalate phthalates EDC endocrine disrupting chemicals low T low Testosterone low T Testosterone hormone hormones

shared by Nathan Goodyear on 16 Aug 14 - No Cached
  • Nathan Goodyear on 16 Aug 14
     
    Phthalate exposure is a cause of low Testosterone in men, women, and children.   In boys 6-12, exposure was associated with a 24-34% reduction in Testosterone.
Nathan Goodyear

Differential Effects of Dehydroepiandrosterone and Testosterone in Prostate and Colon C... - 0 views

press.endocrine.org/...en.2012-2249

testosterone prostate colon colon cancer cancer NGF nerve growth factor dhea dehydroepiandrosterone

shared by Nathan Goodyear on 19 Nov 14 - No Cached
  • Several studies indicate that DHEA may enhance cancer-promoting activities in several prostate cancer cell lines acting as agonist or antagonist for the intracellular AR
  • the estrogenic metabolites of DHEA, 5a-androstane-3b, 17b-diol (3b-Adiol) and E2 bind to estrogen receptors but not to AR
  • no specific receptor has been identified for DHEA
  • ...16 more annotations...
  • Different members of neurotrophins are expressed during cancer progression, suggesting their involvement in cell proliferation, anoikis protection, and malignancy
  • Regulation of the apoptotic machinery in prostate and colon cancer cells by testosterone occurs rapidly and is initiated at the plasma membrane level through specific membrane-binding sites not involving the classical cytoplasmic AR
  • testosterone exerts potent regulatory effects on prostate and colon cancer cell apoptosis
  • Testosterone increased cell death in a dose-dependent manner
  • testosterone antagonizes the prosurvival effects of DHEA in neuronal cells, blocking its binding to NGF receptors
  • treatment of cells with DHEA exerted a strong antiapoptotic effect,
  • Androgens hold a central role in prostate and colon cancer biology
  • elevated levels of DHEA or its sulfate ester DHEA-sulfate in young adults are associated to low incidence of androgen-dependent tumors
  • DHEA may play a protective role in young prostate
  • The decline of DHEA with aging may contribute to prostate cancer progression associated with advanced age
  • DHEA is an effective antiapoptotic factor, reversing the serum deprivation-induced apoptosis in prostate cancer cells (DU145 and LNCaP cell lines) as well as in colon cancer cells
  • NGF appears to exert similar antiapoptotic actions in both prostate and color cancer cells
  • exposure of prostate DU145 and colon Caco2 cancer cells to testosterone totally blocked the protective effects of both DHEA and NGF. These findings suggest that testosterone acts as an antagonist of DHEA and NGF
  • These findings support the hypothesis that testosterone may inhibit cancer cell growth by antagonizing the proliferative, antiapoptotic effects of endogenous factors, such as DHEA or NGF, in the case of prostate and colon cancer cells
  • intratumor hormonal microenvironment may play a critical role in tumor progression.
  • The paracrine interactions of androgens with locally produced NGF may define tumor cell fate
  • Nathan Goodyear on 19 Nov 14
     
    Full article of previously posted abstract.  Cancers are unique.  Not all cancers are alike.  Whether they are tissue specific or not, cancers are unique.  This article describes the uniqueness of DHEA and Testosterone cancer, with particular attention to colon.
Nathan Goodyear

Sources and Significance of Plasma Levels of Catechols and Their Metabolites in Humans - 0 views

jpet.aspetjournals.org/...800.full

dopamine DOPAC catecholamines neurotransmitters epinephrine norepinephrine

shared by Nathan Goodyear on 21 Oct 15 - No Cached
  • Nathan Goodyear on 21 Oct 15
     
    Good review of the sources and metabolism of catecholamines in the blood.
Nathan Goodyear

Rare Occurrence of 3 "H": Hypercalcemia, Hemolytic Anemia and Hodgkin's Lymphoma - 0 views

www.ncbi.nlm.nih.gov/...PMC4925562

Hodgkin's lymphoma Hodgkin's disease hypercalcemia lymphoma

shared by Nathan Goodyear on 21 Aug 18 - No Cached
  • administered zoledronic acid (4 mg). Prednisolone (1 mg/kg/day) was started and simultaneously, she was administered first cycle of ABVD (Adriamycin: 25 mg/m2, Bleomycin: 10 U/m2, Vinblastine: 6 mg/m2 and Dacarbazine: 375 mg/m2), which led to normalisation of serum calcium levels over 4 days and improvement in her hemoglobin levels
  • Etiology of anemia in Hodgkin’s lymphoma is multifactorial. Anemia of chronic disease, decreased red cell survival, infiltration of bone marrow by tumor and marrow suppression by chemotherapy/radiotherapy are the common mechanisms
  • Our case had only a transient response to steroids and chemotherapy. Therefore, she was treated with Rituximab which brought hemolysis under control
  • ...7 more annotations...
  • Hypercalcemia in HL is rare and its incidence has been reported as 0.9, 1.6 and 5.4 % in different series
  • Hypercalcemia of malignancy involves three mechanisms: 1. Humoral hypercalcemia mediated by PTHrP—seen in solid tumors like breast cancer and adult T cell leukemia/lymphoma (ATLL), 2. Direct osteoclast mediated bone resorption due to bony metastasis—seen in solid tumors and multiple myeloma, 3. Calcitriol mediated hypercalcemia—seen in Hodgkin’s and non-Hodgkin’s lymphoma as well as granulomatous disorders like tuberculosis, sarcoidosis, leprosy and disseminated Candidiasis
  • Mechanism of hypercalcemia in HL has long been suggested to involve extra-renal activation of 1α-hydroxylase leading to production of 1, 25(OD)2 Vitamin D3 or Calcitriol, an active metabolite of Vitamin D, which leads to increased re-absorption of calcium and phosphate from intestine, increased osteoclast activation and bone resorption as well as increased phosphate re-absorption in renal tubules
  • The source of 1α-hydroxylase in HL has been postulated as monocytes and macrophages infiltrating the tumor akin to tuberculosis or sarcoidosis and is stimulated by IFN-γ secreted by T-lymphocytes
  • Like sarcoidosis, patients with HL exhibit increased sensitivity to Vitamin D supplements and sunlight, which have been found to precipitate hypercalcemia in these patients
  • Classical biochemical profile in Calcitriol mediated hypercalcemia include: an elevated calcium, normal/slightly elevated phosphate, normal 25(OH) Vitamin D, suppressed PTHrP and PTH, elevated Calcitriol and a normal/increased tubular reabsorption of phosphate
  • not been associated with a poorer prognosis and tends to subside after treatment of the underlying disease
  • Nathan Goodyear on 21 Aug 18
     
    great read on hypercalcemia in hodgkin's lymphoma.
Nathan Goodyear

The Pharmacokinetics and Interactions of Ivermectin in Humans-A Mini-review - 0 views

www.ncbi.nlm.nih.gov/...PMC2751445

Ivermectin

shared by Nathan Goodyear on 19 Mar 18 - No Cached
  • This drug is extensively metabolized by human liver microsomes by cytochrome P450
  • cytochrome P-4503A4, converting the drug to at least 10 metabolites
  • its elimination half-life is around a day
  • ...12 more annotations...
  • second rise in plasma levels (mostly occurring between 6 and 12 h after the dose) suggesting an enterohepatic recycling of the drug
  • Ivermectin is exceptionally potent, with effective dosages levels that are unusually low.
  • the optimal dose of ivermectin is 150 μg/kg, but the frequency of administration is still controversial, ranging from 150 μg/kg once to three times yearly.
  • high lipid solubility of ivermectin, this compound is widely distributed within the body.
  • To interrupt the transmission of onchocerciasis in humans, the combination of ivermectin and doxycycline is highly effective as, in infested patients, the ingestion of the anthelmintic (200 μg/kg, single dose) and the antibacterial (100 mg/kg, daily for 6 weeks)
  • ivermectin interactions with another concurrently administered drugs can occur.
  • This issue becames important, as combination chemotherapy is being used with increasing frequency as resistance to antiparasitic agents is becoming more widespread.
  • haematomatous swellings
  • prothrombin times were significantly above baseline by one week to one month after drug ingestion, suggesting an antagonist effect against vitamin K
  • bleeding disorders were not found in 15,000 patients treated with ivermectin (150 μg/kg)
  • prolonged prothrombin ratios were observed in 148 subjects given ivermectin orally. Although no patients suffered bleeding complications, factor II and VII levels were reduced in most of them, suggesting interference with vitamin K metabolism
  • Ivermectin has a minimal effect on coagulation and concern about mass treatment for this reason appears to be unjustified
  • Nathan Goodyear on 19 Mar 18
     
    Review of Ivermectin as an anti-parasitic.
Nathan Goodyear

Dutasteride affects progesterone metabolizing enzyme activity/expression in human breas... - 0 views

www.sciencedirect.com/...S0960076006001397

hormones progesterone cancer breast cancer 5alpha-pregnane 4-pregnenes progesterone metabolites 5 alpha reductase 5 alpha reductase inhibitors

shared by Nathan Goodyear on 07 Oct 16 - No Cached
  • Nathan Goodyear on 07 Oct 16
     
    Cell culture study finds that 5alpha-reductase inhibition decreased 5alpha-pregnanes and thus inhibited cell proliferation and detachment; this is in contrast to the 4 pregnenes that occur through the enzymes 3alpha-hydroxysteroid oxidoreductase and the 20alpha-hydroxysteroid oxidoreductase, which show anti cell proliferation and cell detachment.
Nathan Goodyear

Activity and expression of progesterone metabolizing 5α-reductase, 20α-hydrox... - 0 views

bmccancer.biomedcentral.com/...1471-2407-3-9

hormones progesterone progesterone metabolites cancer breast cancer 5alpha reductase 5alpha-pregnane 4-pregnene

shared by Nathan Goodyear on 07 Oct 16 - No Cached
  • Nathan Goodyear on 07 Oct 16
     
    cell culture study finds that increased 5alpha reductase activity and resultant 5alpha-pregnanes are associated with breast cancer cell lines.  This is in contrast to the 4-pregnenes.  In fact, decreased 4-pregnenes are found in the same breast cancer cell lines; this suggests decreased 20alpha-HSO and 3alpha-HSO activity.
Nathan Goodyear

DISTRIBUTION OF ASCORBIC ACID, METABOLITES AND ANALOGUES IN MAN AND ANIMALS - Hornig - ... - 0 views

onlinelibrary.wiley.com/...full

vitamin C brain adrenals heart

shared by Nathan Goodyear on 28 Feb 18 - No Cached
  • Nathan Goodyear on 28 Feb 18
     
    The tissues that have the highest concentrations of vitamin C are adrenal, pituitary, brain, heart, pancrease, and kidneys.
Nathan Goodyear

Intravenous Ascorbate as a Tumor Cytotoxic Chemotherapeutic Agent - 0 views

www.seanet.com/...d_hypotheses_1995-v44-p207.htm

vitamin C cancer IV vitamin C ascorbic acid

shared by Nathan Goodyear on 05 Mar 18 - No Cached
  • There is a 10 — 100-fold greater content of catalase in normal cells than in tumor cells
  • induce hydrogen peroxide generation
  • Ascorbic acid and its salts (AA) are preferentially toxic to tumor cells in vitro (6 — 13) and in vivo
  • ...36 more annotations...
  • related to intracellular hydrogen peroxide generation
  • only be obtained by intravenous administration of AA
  • Preferentially kills neoplastic cells
  • Is virtually non-toxic at any dosage
  • Does not suppress the immune system, unlike most chemotherapy agents
  • Increases animal and human resistance to infectious agents by enhancing lymphocyte blastogenesis, enhancing cellular immunity, strengthening the extracellular matrix, and enhancing bactericidal activity of neutrophils and modulation of complement protein
  • Strengthens the structural integrity of the extracellular matrix which is responsible for stromal resistance to malignant invasiveness
  • 1969, researchers at the NCI reported AA was highly toxic to Ehrlich ascites cells in vitro
  • In 1977, Bram et al reported preferential AA toxicity for several malignant melanoma cell lines, including four human-derived lines
  • Noto et al reported that AA plus vitamin K3 had growth inhibiting action against three human tumor cell lines at non-toxic levels
  • Metabolites of AA have also shown antitumor activity in vitro
  • The AA begins to reduce cell proliferation in the tumor cell line at the lowest concentration, 1.76 mg/dl, and is completely cytotoxic to the cells at 7.04 mg/dl
  • the normal cells grew at an enhanced rate at the low dosages (1.76 and 3.52 mg/dl)
  • preferential toxicity of AA for tumor cells. >95% toxicity to human endometrial adenocarcinoma and pancreatic tumor cells (ATCC AN3-CA and MIA PaCa-2) occurred at 20 and 30 mg/dl, respectively.
  • No toxicity or inhibition was demonstrated in the normal, human skin fibroblasts (ATCC CCD 25SK) even at the highest concentration of 50 mg/dl.
  • the use of very high-dose intravenous AA for the treatment of cancer was proposed as early as 1971
  • Cameron and Pauling have published extensive suggestive evidence for prolonged life in terminal cancer patients orally supplemented (with and without initial intravenous AA therapy) with 10 g/day of AA
  • AA, plasma levels during infusion were not monitored,
  • the long-term, oral dosage used in those experiments (10 g/day), while substantial and capable of producing immunostimulatory and extracellular matrix modulation effects, was not high enough to achieve plasma concentrations that are generally cytotoxic to tumor cells in culture
  • This low cytotoxic level of AA is exceedingly rare
  • 5 — 40 mg/dl of AA is required in vitro to kill 100% of tumor cells within 3 days. The 100% kill levels of 30 mg/dl for the endometrial carcinoma cells and 40 mg/dl for the pancreatic carcinoma cells in Figure 2 are typical
  • normal range (95% range) of 0.39-1.13 mg/dl
  • 1 h after beginning his first 8-h infusion of 115 g AA (Merit Pharmaceuticals, Los Angeles, CA), the plasma AA was 3.7 mg/dl and at 5 h was 19 mg/dl. During his fourth 8-h infusion, 8 days later, the 1 h plasma level was 158 mg/dl and 5 h was 185 mg/dl
  • plasma levels of over 100 mg/dl have been maintained in 3 patients for more than 5 h using continuous intravenous infusion
  • In rare instances of patients with widely disseminated and rapidly proliferating tumors, intravenous AA administration (10 — 45 g/day) precipitated widespread tumor hemorrhage and necrosis, resulting in death
  • Although the outcomes were disastrous in these cases, they are similar to the description of tumor-necrosis-factor-induced hemorrhage and necrosis in mice (52) and seem to demonstrate the ability of AA to kill tumor cells in vivo.
  • toxic effects of AA on one normal cell line were observed at 58.36 mg/dl and the lack of side effects in patients maintaining >100 mg/dl plasma levels
  • Although it is very rare, tumor necrosis, hemorrhage, and subsequent death should be the highest priority concern for the safety of intravenous AA for cancer patients.
  • Klenner, who reported no ill effects of dosages as high as 150 g intravenously over a 24-h period
  • Cathcart (55) who describes no ill effects with doses of up to 200 g/d in patients with various pathological conditions
  • following circumstances: renal insufficiency, chronic hemodialysis patients, unusual forms of iron overload, and oxalate stone formers
  • Screening for red cell glucose-6-phosphate dehydrogenase deficiency, which can give rise to hemolysis of red blood cells under oxidative stress (57), should also be performed
  • any cancer therapy should be started at a low dosage to ensure that tumor hemorrhage does not occur.
  • patient is orally supplementing between infusions
  • a scorbutic rebound effect can be avoided with oral supplementation. Because of the possibility of a rebound effect, measurement of plasma levels during the periods between infusions should be performed to ensure that no such effect takes place
  • Every effort should be made to monitor plasma AA levels when a patient discontinues intravenous AA therapy.
  • Nathan Goodyear on 05 Mar 18
     
    Older study, 1995, but shows the long-standing evidence that IVC preferentially is cytotoxic to cancer cells.`
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