What is the optimum thiamine dose to treat or prevent Wernicke's encephalopathy or Wernicke-Korsakoff syndrome? Results of a randomized controlled trial.

BACKGROUND: The primary cause of Wernicke-Korsakoff syndrome (WKS) is thiamine deficiency, and more than 90% of cases are reported in alcohol-dependent patients. While observational studies show parenteral thiamine administration drastically reduced WKS-related mortality, relevant treatment trials have never been conducted to determine the optimum thiamine dose. METHODS: Two double-blind, parallel groups, randomized controlled trials (RCTs) were conducted to determine the optimal thiamine dose required for (1) the prevention of Wernicke's encephalopathy (WE), the acute phase of WKS, in asymptomatic but "at-risk" alcohol misuse patients (Study 1) and (2) the treatment of WE in symptomatic alcohol misuse patients (Study 2). Each study had a dosage regimen comprising three parenteral thiamine doses that were allocated at a ratio of 1:1:1. Study 1: Asymptomatic At-Risk patients (N = 393) received either 100 mg daily, 100 mg thrice daily, or 300 mg thrice daily, for 3 days. Study 2: Symptomatic patients (N = 127) received either 100 mg thrice daily, 300 mg thrice daily, or 500 mg thrice daily, for 5 days. Cognitive function was the primary outcome, assessed using the Rowland Universal Dementia Assessment Scale, two Cogstate subtests, and an adapted Story Memory Recall test. Secondary analyses examined differences in neurological function (ataxia, oculomotor abnormalities, and confusion) at follow-up. RESULTS: No significant differences were observed between any of the dosage conditions for either Study 1 or Study 2 on cognition or neurological functioning. This real-world study found that having a clinically unwell target population with high comorbidity and multiple presentations, coupled with challenges in cross-cultural assessment is likely to complicate RCT findings. CONCLUSIONS: The results of this study showed no clear benefit of high dose thiamine over intermediate or lower doses of thiamine, over the time intervals examined, for the treatment and prevention of cognitive and neurological abnormalities related to WKS. Several study limitations temper the interpretation of these findings. Nevertheless, the absence of conclusive evidence for the superiority of high-dose thiamine supports a recommendation for patient-specific treatment, while ensuring that the potential impact of other biochemical factors (e.g., magnesium and other B vitamin deficiencies) are considered and corrected if necessary.

Paeoniflorin and liquiritin, two major constituents in Chinese herbal formulas used to treat hyperprolactinemia-associated disorders, inhibits prolactin secretion in prolactinoma cells by different mechanisms.

ETHNOPHARMACOLOGICAL RELEVANCE: Paeoniflorin and liquiritin are major constituents in some Chinese herbal formulas, such as Yiru Tiaojing (YRTJ) Granule (a hospitalized preparation) and Peony-Glycyrrhiza Decoction, used for hyperprolactinemia-associated disorders. AIM OF THE STUDY: To investigate the effect of paeoniflorin and liquiritin on prolactin secretion. MATERIALS AND METHODS: The effect of YRTJ Granule on metoclopramide-induced hyperprolactinemia was tested in rats. Paeoniflorin and liquiritin in the YRTJ Granule extract were identified and quantified by HPLC. The effects of paeoniflorin and liquiritin on prolactin secretion were examined in prolactinoma cells that were identified morphologically and by Western blot. The concentration of prolactin was determined by ELISA. The gene expression was analyzed by Western blot. RESULTS: YRTJ Granule ameliorated metoclopramide-induced hyperprolactinemia in rats. The contents of paeoniflorin and liquiritin in YRTJ Granule were 7.43 and 2.05mg/g extract, respectively. Paeoniflorin, liquiritin and bromocriptine (a dopamine D2 receptor (D2R) agonist) decreased prolactin concentration in MMQ cells expressing D2R. However, the effect of liquiritin and bromocriptine was abolished in GH3 cells lacking D2R expression. Interestingly, paeoniflorin still decreased prolactin concentration in GH3 cells in the same manner. Furthermore, paeoniflorin suppressed prolactin protein expression, and was without effect on D2R protein expression in both MMQ and GH3 cells. CONCLUSIONS: The present results suggest that paeoniflorin and liquiritin play a role in YRTJ Granule-elicited improvement of hyperprolactinemia. While the effect of liquiritin is D2R-dependent, paeoniflorin D2R-independently inhibits prolactin secretion in prolactinoma cells that may especially benefit the hyperprolactinemic patients who are refractory to dopaminergic therapies.

Jiangzhi Capsule improves fructose-induced insulin resistance in rats: Association with repair of the impaired sarcolemmal glucose transporter-4 recycling.

ETHNOPHARMACOLOGICAL RELEVANCE: Jiangzhi Capsule, originated from an experienced formula in traditional Chinese Medicine, has been listed and used for the management of metabolic abnormalities in Australia for a long time. To better understand Jiangzhi Capsule, this study investigated its effect on insulin resistance. MATERIALS AND METHODS: Male rats were treated with liquid fructose in their drinking water over 14 weeks. Jiangzhi Capsule was co-administered (once daily, by oral gavage) during the last 7 weeks. Indexes of lipid and glucose homeostasis were determined enzymatically, by ELISA and/or histologically. Gene expression was analyzed by real-time PCR, Western blot and/or immunohistochemistry. RESULTS: Treatment with Jiangzhi Capsule (100mg/kg) attenuated fructose overconsumption-induced increases in basal plasma insulin concentrations, the homeostasis model assessment of insulin resistance index and the adipose tissue insulin resistance index in rats. The increased plasma glucose concentrations during oral glucose tolerance test were also inhibited. Furthermore, Jiangzhi Capsule had a trend to attenuate the decreased ratios of glucose and non-esterified fatty acids to plasma insulin concentrations. Mechanistically, this insulin-sensitizing action was accompanied by normalization of the downregulated sarcolemmal glucose transporter (GLUT)-4 protein expression and the decreased phosphorylated Akt to total Akt protein ratio in gastrocnemius. CONCLUSIONS: These results suggest that Jiangzhi Capsule ameliorates fructose-induced insulin resistance with a link to repair of the impaired sarcolemmal GLUT-4 recycling through modulation of the ratio of phosphorylated Akt to total Akt in gastrocnemius. Our findings provide an evidence-based and mechanistic understanding of Jiangzhi Capsule for the management of insulin resistance-associated disorders.

Treatment of rats with Jiangzhi Capsule improves liquid fructose-induced fatty liver: modulation of hepatic expression of SREBP-1c and DGAT-2.

BACKGROUND: Jiangzhi Capsule is an Australian listed patented traditional Chinese medicine and has been used for management of lipid abnormalities over the past 10 years. To obtain a better understanding regarding Jiangzhi Capsule, the present study investigated the effects and underlying mechanisms of Jiangzhi Capsule on chronic fructose overconsumption-induced lipid abnormalities. METHODS: Male rats were treated with liquid fructose in their drinking water over 14 weeks. Jiangzhi Capsule was co-administered (once daily, by oral gavage) during the last 7 weeks. Indexes of lipid and glucose homeostasis were determined enzymatically, by ELISA and/or histologically. Gene expression was analyzed by real-time PCR, Western blot and/or immunohistochemistry. RESULTS: Treatment with Jiangzhi Capsule (100 mg/kg) attenuated fructose-induced excessive triglyceride accumulation and Oil Red O-stained area in the liver. This effect was accompanied by amelioration of hyperinsulinemia. There was no significant difference in intakes of fructose and chow, and body weight between fructose control and fructose Jiangzhi Capsule-treated groups. Mechanistically, Jiangzhi Capsule downregulated fructose-stimulated hepatic overexpression of sterol regulatory element binding protein (SREBP)-1/1c at the mRNA and protein levels. Accordingly, the SREBP-1c downstream genes, acetyl-CoA carboxylase-1 and stearoyl-CoA desaturase-1, were also inhibited. In addition, acyl-coenzyme A:diacylglycerol acyltransferase (DGAT)-2 expression at the mRNA and protein levels in the liver was also inhibited after Jiangzhi Capsule treatment. In contrast, Jiangzhi Capsule affected neither carbohydrate response element binding protein, peroxisome proliferator-activated receptor (PPAR)-gamma and DGAT-1, nor PPAR-alpha and its target genes. CONCLUSIONS: These findings demonstrate the anti-steatotic action of Jiangzhi Capsule in fructose-fed rats, and modulation of hepatic SREBP-1c and DGAT-2 involved in hepatic de novo synthesis of fatty acids and triglyceride, respectively. Our findings provide an evidence-based and mechanistic understanding of Jiangzhi Capsule supporting its application for the prevention and/or treatment of fatty liver and its associated disorders in clinical practice.

Hypomagnesaemia and its potential impact on thiamine utilisation in patients with alcohol misuse at the Alice Springs Hospital.

INTRODUCTION AND AIMS: Alcohol rapidly reduces thiamine among alcohol-dependent individuals. Poor diet and alcohol's impact on absorption, storage, activation and excretion of thiamine are thought to be the mechanisms. Previous literature identifies magnesium as an important cofactor in thiamine utilisation, which might also be compromised in alcohol dependent patients. The aim was to describe the thiamine status and clinical profile for a sample of heavy alcohol users entering the Alice Springs Hospital in the Northern Territory of Australia and to examine the relationship between thiamine deficiency, magnesium deficiency and cognitive functioning. DESIGN AND METHODS: Cross-sectional study examining thiamine pyrophosphate (TPP) and magnesium concentrations for a sample of 62 males and 43 females (N = 105; n = 88 Aboriginal, n = 13 non-Indigenous). Cognition was assessed using the Rowland Universal Dementia Assessment Scale. RESULTS: TPP concentrations were within or above the reference range. Aboriginal patients had significantly lower TPP than non-Indigenous patients. A marginally significant difference was found between individuals with thiamine supplementation recorded within the previous 20 days compared with those without. Mean serum magnesium was in the low normal range with magnesium deficiency (i.e. <0.80 mmol L(-1)) present in 48% of those tested. Serum magnesium (but not TPP) concentrations correlated positively with cognitive test scores. DISCUSSION AND CONCLUSIONS: Despite increased exposure to risk factors for Wernicke Korsakoff Syndrome, no patient had TPP concentrations below the reference range. High patient readmission and aggressive thiamine treatment policies may explain this finding. However, low magnesium may be prevalent and could contribute to impaired thiamine utilisation.

Single-molecule conformational dynamics of a biologically functional hydroxocobalamin riboswitch.

Riboswitches represent a family of highly structured regulatory elements found primarily in the leader sequences of bacterial mRNAs. They function as molecular switches capable of altering gene expression; commonly, this occurs via a conformational change in a regulatory element of a riboswitch that results from ligand binding in the aptamer domain. Numerous studies have investigated the ligand binding process, but little is known about the structural changes in the regulatory element. A mechanistic description of both processes is essential for deeply understanding how riboswitches modulate gene expression. This task is greatly facilitated by studying all aspects of riboswitch structure/dynamics/function in the same model system. To this end, single-molecule fluorescence resonance energy transfer (smFRET) techniques have been used to directly observe the conformational dynamics of a hydroxocobalamin (HyCbl) binding riboswitch (env8HyCbl) with a known crystallographic structure.1 The single-molecule RNA construct studied in this work is unique in that it contains all of the structural elements both necessary and sufficient for regulation of gene expression in a biological context. The results of this investigation reveal that the undocking rate constant associated with the disruption of a long-range kissing-loop (KL) interaction is substantially decreased when the ligand is bound to the RNA, resulting in a preferential stabilization of the docked conformation. Notably, the formation of this tertiary KL interaction directly sequesters the Shine-Dalgarno sequence (i.e., the ribosome binding site) via base-pairing, thus preventing translation initiation. These results reveal that the conformational dynamics of this regulatory switch are quantitatively described by a four-state kinetic model, whereby ligand binding promotes formation of the KL interaction. The results of complementary cell-based gene expression experiments conducted in Escherichia coli are highly correlated with the smFRET results, suggesting that KL formation is directly responsible for regulating gene expression.

A small-molecule inhibitor of D-cyclin transactivation displays preclinical efficacy in myeloma and leukemia via phosphoinositide 3-kinase pathway.

D-cyclins are universally dysregulated in multiple myeloma and frequently overexpressed in leukemia. To better understand the role and impact of dysregulated D-cyclins in hematologic malignancies, we conducted a high-throughput screen for inhibitors of cyclin D2 transactivation and identified 8-ethoxy-2-(4-fluorophenyl)-3-nitro-2H-chromene (S14161), which inhibited the expression of cyclins D1, D2, and D3 and arrested cells at the G(0)/G(1) phase. After D-cyclin suppression, S14161 induced apoptosis in myeloma and leukemia cell lines and primary patient samples preferentially over normal hematopoietic cells. In mouse models of leukemia, S14161 inhibited tumor growth without evidence of weight loss or gross organ toxicity. Mechanistically, S14161 inhibited the activity of phosphoinositide 3-kinase in intact cells and the activity of the phosphoinositide 3-kinases α, ß, δ, and γ in a cell-free enzymatic assay. In contrast, it did not inhibit the enzymatic activities of other related kinases, including the mammalian target of rapamycin, the DNA-dependent protein kinase catalytic subunit, and phosphoinositide-dependent kinase-1. Thus, we identified a novel chemical compound that inhibits D-cyclin transactivation via the phosphoinositide 3-kinase/protein kinase B signaling pathway. Given its potent antileukemia and antimyeloma activity and minimal toxicity, S14161 could be developed as a novel agent for blood cancer therapy.

Randomized double blind placebo-controlled trial of a Chinese herbal therapy (CH100) in chronic hepatitis C.

BACKGROUND AND AIM: Hepatitis C virus (HCV) is a common infection with serious health consequences. Alternative therapies are often used for hepatitis C. The aim of the present study was to examine CH100, a Chinese herbal remedy, for efficacy in therapy of chronic HCV. METHODS: A randomized double blind placebo-controlled study in a tertiary outpatient clinic of CH100 over 24 weeks with 24 weeks follow-up in patients with chronic HCV infection. Alanine aminotransferase (ALT), HCV-RNA, quality of life (by SF-36) and side-effects were examined regularly. Ninety-seven patients were enrolled of which 91 were suitable for analysis. RESULTS: No significant differences were observed between patients receiving CH100 (n = 61) or placebo (n = 30) at baseline or during follow-up in either ALT or viral titer. However, patients receiving CH100 had a fall in mean ALT over time (P = 0.05 at week 4, P = 0.26 at week 12, and P = 0.04 at week 24), with reversion to baseline during post-treatment follow up. No significant side-effects were observed although mild complaints were common. Quality of life scores improved in both groups with time, and bodily pain significantly improved in CH100 recipients. CONCLUSION: CH100 appears to be no better than placebo in the treatment of patients with chronic HCV infection.

Complementary and alternative medicine in the treatment of chronic liver disease.

Interest in and use of complementary and alternative medicines (CAM) in the treatment of chronic liver diseases has increased in the past decade. However, this has not been supported by a significant increase in sound clinical research evidence for their efficacy. The research literature is growing, providing improved knowledge on population use of CAM, possible mechanisms of action of a large range of complementary and alternative medications, and possible specific indications for these agents in patients with liver disease. Although curative potential for CAM has not been documented consistently in any liver disorder, it is possible to identify anti-inflammatory activity and cytoprotective capacity for a number of agents from different branches of the world of CAM. Evidence grows for potential harm from an increasing number of compounds. Concurrently, clarity is increasing in relation to which specific constituents cause the harm and the mechanisms by which damage is produced.