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Apigenin suppresses cancer cell growth through ERbeta.: Neoplasia. 2006 Nov;8(11):896-904 Authors: Mak P, Leung YK, Tang WY, Harwood C, Ho SM

Two flavonoids, genistein and apigenin, have been implicated as chemopreventive agents against prostate and breast cancers. However, the mechanisms behind their respective cancer-protective effects may vary significantly. The goal of this study was to determine whether the antiproliferative action of these flavonoids on prostate (DU-145) and breast (MDA-MB-231) cancer cells expressing only estrogen receptor (ER) beta is mediated by this ER subtype. It was found that both genistein and apigenin, although not 17beta-estradiol, exhibited antiproliferative effects and proapoptotic activities through caspase-3 activation in these two cell lines. In yeast transcription assays, both flavonoids displayed high specificity toward ERbeta transactivation, particularly at lower concentrations. However, in mammalian assay, apigenin was found to be more ERbeta-selective than genistein, which has equal potency in inducing transactivation through ERalpha and ERbeta. Small interfering RNA-mediated downregulation of ERbeta abrogated the antiproliferative effect of apigenin in both cancer cells but did not reverse that of genistein. Our data unveil, for the first time, that the anticancer action of apigenin is mediated, in part, by ERbeta. The differential use of ERalpha and ERbeta signaling for transaction between genistein and apigenin demonstrates the complexity of phytoestrogen action in the context of their anticancer properties.

Anticancer effects of Chinese herbal medicine, science or myth?: J Zhejiang Univ Sci B. 2006 Dec;7(12):1006-14 Authors: Ruan WJ, Lai MD, Zhou JG

Currently there is considerable interest among oncologists to find anticancer drugs in Chinese herbal medicine (CHM). In the past, clinical data showed that some herbs possessed anticancer properties, but western scientists have doubted the scientific validity of CHM due to the lack of scientific evidence from their perspective. Recently there have been encouraging results, from a western perspective, in the cancer research field regarding the anticancer effects of CHM. Experiments showed that CHM played its anticancer role by inducing apoptosis and differentiation, enhancing the immune system, inhibiting angiogenesis, reversing multidrug resistance (MDR), etc. Clinical trials demonstrated that CHM could improve survival, increase tumor response, improve quality of life, or reduce chemotherapy toxicity, although much remained to be determined regarding the objective effects of CHM in human in the context of clinical trials. Interestingly, both laboratory experiments and clinical trials have demonstrated that when combined with chemotherapy, CHM could raise the efficacy level and lower toxic reactions. These facts raised the feasibility of the combination of herbal medicines and chemotherapy, although much remained to be investigated in this area.

Reporting associations between dietary supplements and adverse events.: Mayo Clin Proc. Author: Michael McGuffin
To the Editor: The article by Gange et al, published in the April 2006 issue of Mayo Clinic Proceedings, purported to document an association between bitter orange peel extract and variant angina in a borderline-obese 57-year-old man. However, the authors’ identification of bitter orange as the offending ingredient must be considered speculative. It would be no more accurate to assume that any of the other 9 ingredients in the supplement, or the drugs, or other supplements the patient was taking concomitantly, were the cause of the patient’s angina.

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Herbal medicine: women's views, knowledge and interaction with doctors: a qualitative study.: BMC Complement Altern Med. 2006;6:40 Authors: Vickers KA, Jolly KB, Greenfield SM

BACKGROUND: There is growing concern that serious interactions are occurring between prescribed/over the counter and herbal medicines and that there is a lack of disclosure of herbal use by patients to doctors. This study explores women's perspectives about the safety of herbal remedies, herb-drug interactions and communication with doctors about herbal medicines. METHODS: Qualitative, cross-sectional study, with purposive sampling which took place in Cheshire, UK. Eighteen in depth semi-structured interviews were conducted with female herbal medicine users aged 18 years and above. RESULTS: The large majority did not inform their GPs of their use of herbal medicines. This was due to lack of physician enquiry, perception of importance and fear of a negative response. Several women were not aware that herbal remedies could interact with prescribed or over the counter medicines. Of the women who had experienced adverse effects none had reported them, believing them of low importance. CONCLUSION: The women had little knowledge about herb-drug interactions and rarely disclosed use of herbal medicines to their doctor. Doctors' communication and openness regarding herbal medicines needs to improve and there should be increased access to accurate information on herbal medicines in the public and health care domain.

An experimental study of sexual function improving effect of Myristica fragrans Houtt. (nutmeg).: BMC Complement Altern Med. 2005;5:16 Authors: Tajuddin , Ahmad S, Latif A, Qasmi IA, Amin KM

BACKGROUND: Myristica fragrans Houtt. (nutmeg) has been mentioned in Unani medicine to be of value in the management of male sexual disorders. The present study was undertaken to evaluate the aphrodisiac effect of 50% ethanolic extract of nutmeg along with its likely adverse effects and acute toxicity using various animal models. METHODS: The suspension of the extract was administered (100, 250 and 500 mg/kg, p.o.) to different groups of male rats daily for seven days. The female rats involved in mating were made receptive by hormonal treatment. The general mating behaviour, libido and potency were studied and compared with the standard reference drug sildenafil citrate. Likely adverse effects and acute toxicity of the extract were also evaluated. RESULTS: Oral administration of the extract at the dose of 500 mg/kg, produced significant augmentation of sexual activity in male rats. It significantly increased the Mounting Frequency, Intromission Frequency, Intromission Latency and caused significant reduction in the Mounting Latency and Post Ejaculatory Interval. It also significantly increased Mounting Frequency with penile anaesthetization as well as Erections, Quick Flips, Long Flips and the aggregate of penile reflexes with penile stimulation. The extract was also observed to be devoid of any adverse effects and acute toxicity. CONCLUSION: The resultant significant and sustained increase in the sexual activity of normal male rats without any conspicuous adverse effects indicates that the 50% ethanolic extract of nutmeg possesses aphrodisiac activity, increasing both libido and potency, which might be attributed to its nervous stimulating property. The present study thus provides a scientific rationale for the traditional use of nutmeg in the management of male sexual disorders.

Preliminary evidence of mitochondrial dysfunction associated with post-infective fatigue after acute infection with Epstein Barr Virus

Background: Acute infectious diseases are typically accompanied by non-specific symptoms including fever, malaise, irritability and somnolence that usually resolve on recovery. However, in some individuals these symptoms persist in what is commonly termed post-infective fatigue. The objective of this pilot study was to determine the gene expression correlates of post-infective fatigue following acute Epstein Barr virus (EBV) infection. Methods: We followed 5 people with acute mononucleosis who developed post-infective fatigue of more than 6 months duration and 5 HLA-matched control subjects who recovered within 3 months. Subjects had peripheral blood mononuclear cell (PBMC) samples collected at varying time points including at diagnosis, then every 2 weeks for 3 months, then every 3 months for a year. Total RNA was extracted from the PBMC samples and hybridized to microarrays spotted with 3,800 oligonucleotides. Results: Those who developed post-infective fatigue had gene expression profiles indicative of an altered host response during acute mononucleosis compared to those who recovered uneventfully. Several genes including ISG20 (interferon stimulated gene), DNAJB2 (DnaJ [Hsp40] homolog and CD99), CDK8 (cyclin-dependent kinase 8), E2F2 (E2F transcription factor 2), CDK8 (cyclin-dependent kinase 8), and ACTN2 (actinin, alpha 2), known to be regulated during EBV infection, were differentially expressed in post-infective fatigue cases. Several of the differentially expressed genes affect mitochondrial functions including fatty acid metabolism and the cell cycle. Conclusions: These preliminary data provide insights into alterations in gene transcripts associated with the varied clinical outcomes from acute infectious mononucleosis.

Reduction in the risk of human breast cancer by selective cyclooxygenase-2 (COX-2) inhibitors.

Background: Epidemiologic and laboratory investigations suggest that nonsteroidal anti-inflammatory drugs (NSAIDs) have chemopreventive effects against breast cancer due to their activity against cyclooxygenase-2 (COX-2), the rate-limiting enzyme of the prostaglandin cascade. Methods: We conducted a case control study of breast cancer designed to compare effects of selective and non-selective COX-2 inhibitors. A total of 323 incident breast cancer patients were ascertained from the James Cancer Hospital, Columbus, Ohio, during 2003-2004 and compared with 649 cancer free controls matched to the cases at a 2:1 ratio on age, race, and county of residence. Data on the past and current use of prescription and over the counter medications and breast cancer risk factors were ascertained using a standardized risk factor questionnaire. Effects of COX-2 inhibiting agents were quantified by calculating odds ratios (OR) and 95% confidence intervals. Results: Results showed significant risk reductions for selective COX-2 inhibitors as a group (OR=0.29, 95% CI=0.14-0.59), regular aspirin (OR=0.49, 95% CI = 0.26-0.94), and ibuprofen or naproxen (0.36, 95% CI= 0.18-0.72). Acetaminophen, a compound with negligible COX-2 activity and low dose aspirin (81 mg) produced no significant change in the risk of breast cancer. Conclusions: Selective COX-2 inhibitors (celecoxib and rofecoxib) were only recently approved for use in 1999, and rofecoxib (Vioxx) was withdrawn from the marketplace in 2004. Nevertheless, even in the short window of exposure to these compounds, the selective COX-2 inhibitors produced a significant (71%) reduction in the risk of breast cancer, underscoring their strong potential for breast cancer chemoprevention.

Pharmacokinetics of isoflavones, daidzein and genistein, after ingestion of soy beverage compared with soy extract capsules in postmenopausal Thai women.: BMC Clin Pharmacol. 2005;5(1):2 Authors: Anupongsanugool E, Teekachunhatean S, Rojanasthien N, Pongsatha S, Sangdee C

BACKGROUND: Isoflavones from soybeans may provide some beneficial impacts on postmenopausal health. The purpose of this study was to compare the pharmacokinetics and bioavailability of plasma isoflavones (daidzein and genistein) after a single dose of orally administered soy beverage and soy extract capsules in postmenopausal Thai women. METHODS: We conducted a randomized two-phase crossover pharmacokinetic study in 12 postmenopausal Thai women. In the first phase, each subject randomly received either 2 soy extract capsules (containing daidzin : genistin = 7.79 : 22.57 mg), or soy beverage prepared from 15 g of soy flour (containing daidzin : genistin = 9.27 : 10.51 mg). In the second phase, the subjects received an alternative preparation in the same manner after a washout period of at least 1 week. Blood samples were collected immediately before and at 0.5, 1, 2, 4, 6, 8, 10, 12, 24 and 32 h after administration of the soy preparation in each phase. Plasma daidzein and genistein concentrations were determined by using high performance liquid chromatography (HPLC). The pharmacokinetic parameters of daidzein and genistein, i.e. maximal plasma concentration (Cmax), time to maximal plasma concentration (Tmax), area under the plasma concentration-time curve (AUC) and half-life (t1/2), were estimated using the TopFit version 2.0 software with noncompartmental model analysis. RESULTS: There were no significant differences in the mean values of Cmax/dose, AUC0-32/dose, AUC0- proportional, variant/dose, Tmax, and t1/2 of genistein between both preparations. For pharmacokinetic parameters of daidzein, the mean values of Cmax/dose, Tmax, and t1/2 did not significantly differ between both preparations. Nonetheless, the mean AUC0-32/dose and AUC0- proportional, variant/dose after administration of soy extract capsules were slightly (but significantly, p < 0.05) higher than those of soy beverage. CONCLUSION: The bioavailability of daidzein, which was adjusted for the administered dose (AUC/dose), following a single oral administration of soy beverage was slightly (but significantly) less than that of soy extract capsules, whereas, the bioavailability adjusted for administered dose of genistein from both soy preparations were comparable. The other pharmacokinetic parameters of daidzein and genistein, including Cmax adjusted for the dose, Tmax and t1/2, were not different between both soy preparations.

Licorice: a possible anti-inflammatory and anti-ulcer drug.: AAPS PharmSciTech. 2005;6(1):E74-82 Authors: Aly AM, Al-Alousi L, Salem HA

The purpose of this investigation was to study the anti-inflammatory activities of both glycerrhitinic acid (GA) and the aqueous licorice extract (ALE) in comparison with diclofenac sodium (DS) (10 mg/kg), using the carrageenan-induced paw edema model in male albino rats. In addition, the anti-ulcer activities of ALE, famotidine (FT), and a combination of ALE and FT using indomethacin-induced ulceration technique in rat stomach were investigated. Conventional DS tablets containing GA, as well as DS chewable tablets containing either GA or ALE with different tastes were prepared. Also, rapidly disintegrating FT tablets were prepared using direct compression and camphor sublimation methods. ALE or GA produced significant anti-inflammatory activity similar to DS, and when taken concomitantly, there is no possible antagonism. The anti-ulcer activity of licorice was found to be similar to that of FT in indomethacin-induced ulceration technique in rat stomach. Combination therapy of both FT and licorice showed higher anti-ulcer activity than either of them alone. Generally, tablets containing the crosslinked sodium carboxymethyl cellulose (AcDisol) showed more rapidly disintegrating effect than those including Sodium starch glycolate (Primojel). The oral disintegration was very rapid for all the tested formulations. Also, the amount of FT absorbed from the oral cavity was nearly 9 from 10 mg theoretically present in each formula. It could be concluded that both GA and ALE have anti-inflammatory activity comparable with DS. It may be recommended to add ALE to either FT or diclofinac for more effective anti-inflammatory or anti-ulcer formulations, respectively.

Melatonin, immune function and aging: SC Immunity & Ageing 2005. Venkatramanujam Srinivasan, Georges J.M. Maestroni, Cardinali D, Esquifino AI, Pandi-Perumal SR, Miller

Aging is associated with a decline in immune function (immunosenescence), a situaton known to correlate with increased incidence of cancer, infections and degenerative diseases. Innate, cellular and humoral immunity all exhibit increased deterioration with age. A decrease in functional competence of individual natural killer (NK) cells is found with advancing age. Macrophages and granulocytes show functional decline in aging as evidenced by their diminished phagocytic activity and impairment of superoxide generation. There is also marked shift in cytokine profile, e.g., CD3+ and CD4+ cells decline in number whereas CD8+ cells increase in elderly individuals. A decline in organ specific antibodies occurs causing reduced humoral responsiveness. Circulating melatonin decreases with age and in recent years much interest has been focussed on its immunomodulatory effect. Melatonin stimulates the production of progenitor cells for granulocytes-macrophages. It also stimulates the production of NK cells and CD4+ cells and inhibits CD8+ cells. The production and release of various cytokines from NK cells and T-helper lymphocytes also are enhanced by melatonin. Melatonin presumably regulates immune function by acting on the immune-opioid network, by affecting G protein-cAMP signal pathway and by regulating intracellular glutathione levels. Melatonin has the potential therapeutic value to enhance immune function in aged individuals and in patients in an immunocompromised state.