Results Of Human Clinical Trials Research Articles

Vaccines as Immunotherapies for Substance Use Disorders.

Substance use disorders (SUD) present a worldwide challenge with few effective therapies except for the relative efficacy of opioid pharmacotherapies, despite limited treatment access. However, the proliferation of illicit fentanyl use initiated a dramatic and cascading epidemic of lethal overdoses. This rise in fentanyl overdoses regenerated an interest in vaccine immunotherapy, which, despite an optimistic start in animal models over the past 50 years, yielded disappointing results in human clinical trials of vaccines against nicotine, stimulants (cocaine and methamphetamine), and opioids. After a brief review of clinical and selected preclinical vaccine studies, the "lessons learned" from the previous vaccine clinical trials are summarized, and then the newest challenge of a vaccine against fentanyl and its analogs is explored. Animal studies have made significant advances in vaccine technology for SUD treatment over the past 50 years, and the resulting anti-fentanyl vaccines show remarkable promise for ending this epidemic of fentanyl deaths.

Certainty and uncertainty in the biological activities of resveratrol

AbstractResveratrol is a nonflavonoid polyphenolic compound with a chemical structure consisting of two aromatic rings linked by a methylene bridge. It exists in two primary isomers and has a broad range of desirable biological activities, including antioxidant, anti‐inflammatory, antidiabetic, cardioprotective, and antitumor activities. Some antioxidant properties of resveratrol are known with certainty, such as its potential to positively impact cardiovascular health, inflammation, and the metabolism. On the other hand, many uncertainties and controversies plague its efficacy, including issues related to its bioavailability, dosing, human clinical trial results, interactions with other food components and drugs, and individual variability. In brief, although promising results have been observed in in vitro and in vivo studies, the translation of these findings to human health remains uncertain. Many human clinical trials on resveratrol are ongoing or have proven inconclusive, making it challenging to definitively determine its efficacy for specific health conditions and its dose and duration of treatment. Resveratrol may interact with medications and have varying effects on individuals. In conclusion, it is essential to approach resveratrol with a balanced perspective, consulting with healthcare professionals, and considering the evolving scientific evidence when making decisions regarding its clinical use.

Pancreatic biopsy evaluation with nsCanary: A “smart ROSE” device for feedback on sample adequacy and cancer presence in endoscopic biopsies—Initial human clinical trial results.

618 Background: Pancreatic cancer (PC) accounts for 0.5 million new cases and 4.7% of the world's cancer-related deaths in 2020. Endoscopic ultrasound (EUS) guided fine needle biopsies (FNB) are the current standard of care for confirming suspicious lesions, however the diagnostic accuracy is reported below 70%. Rapid on-site evaluation (ROSE) improves the diagnostic performances of biopsies to reduce the number of needle passes, complication rates, and the need for additional procedures. However, availability of an on-site pathologist is often not feasible. NovaScan has pioneered the use of an impedance spectroscopy biomarker for cancer detection in different tissues based on the Cole Relaxation Frequency (CRF). NovaScan has developed the nsCanary, a ”smart ROSE” device that assesses PC presence in FNBs obtained during endoscopic procedures ex vivo, in real-time and on-site, without altering the tissue sample or affecting the workflow. Methods: Data were collected in a double-blind, IRB approved study from a cohort of 53 patients (28 males, 25 females) undergoing EUS procedures for suspected pancreatic lesions at the Texas International Endoscopy Center. FNBs were performed with a 22 gauge biopsy from a transduodenal approach. Each biopsy sample was transferred onto a disposable strainer allowing for any excess fluid to drain. An electrode for scanning was placed onto the core samples for data collection with the nsCanary a low cost, portable device used in the operating room. CRF is measured in the 1 kHz - 10 MHz frequency range via custom-designed hardware and assessment of the sample is completed in a few seconds. Subsequently, the sample is flushed into a pathology jar to undergo the standard workflow for cytology. The algorithm for extracting the CRF from the measurement was developed based on our previous preclinical study with transgenic KPC mice Samples with a CRF below 1 MHz were considered noncancerous, while CRF values above 1MHz or the absence of a CRF reading were considered cancerous. Results: PC assessment provided by nsCanary was validated against pathology outcomes for each biopsy sample. Findings showing a sensitivity of 86.7% and a specificity of 84.2% are reported in the table. Conclusions: We believe the nsCanary device will provide immediate feedback to the endoscopist on cancer presence and on the adequacy of the sample. This device is intended to support the decision-making process, by enabling clinicians to overcome the challenge of proving cancer presence during the first biopsy procedure, ultimately avoiding revisits and unnecessary trauma.[Table: see text]

Therapeutics of managing reduced red cell mass associated with chronic kidney disease – Is there a case for earlier intervention?

Reduced red cell mass is a poor prognostic indicator in chronic kidney disease (CKD) patients. Whilst overt anaemia impacts on the quality of life of patients with CKD, lowered red cell mass may also compromise oxygen delivery to proximal tubular cells and contribute to progressive kidney injury. Epidemiological data from cats with CKD support this hypothesis although controlled interventional studies involving drugs that raise red cell mass in trials designed to test this hypothesis are lacking in both human and veterinary medicine. Recombinant analogues of erythropoietin (EPO) are currently standard of care for human CKD patients where low red cell mass impacts on their quality of life. Resistance to EPO is encountered in 20% to 40% of patients treated, probably due to functional iron deficiency, reflecting the difficulties of managing iron deficiency associated with the chronic inflammation of CKD. Similar issues are likely faced in managing anaemia in feline CKD although published data on the use of human EPO analogues are limited as such treatment in cats risks antibody formation resulting in red cell aplasia and transfusion dependency and so is reserved for late stage cases only. This article reviews the recent alternative therapeutic approach to increase red cell mass using HIF-prolyl hydroxylase inhibitors and explains their mode of action and theoretical advantages over EPO analogues in the context of iron metabolism. The results of human clinical trials and the potential benefit of adopting this approach in feline CKD patients are discussed.

Characterization of Three Variants of SARS-CoV-2 In Vivo Shows Host-Dependent Pathogenicity in Hamsters, While Not in K18-hACE2 Mice.

Animal models are used in preclinical trials to test vaccines, antivirals, monoclonal antibodies, and immunomodulatory drug therapies against SARS-CoV-2. However, these drugs often do not produce equivalent results in human clinical trials. Here, we show how different animal models infected with some of the most clinically relevant SARS-CoV-2 variants, WA1/2020, B.1.617.2/Delta, B.1.1.529/Omicron, and BA5.2/Omicron, have independent outcomes. We show that in K18-hACE2 mice, B.1.617.2 is more pathogenic, followed by WA1, while B.1.1.529 showed an absence of clinical signs. Only B.1.1.529 was able to infect C57BL/6J mice, which lack the human ACE2 receptor. B.1.1.529-infected C57BL/6J mice had different T cell profiles compared to infected K18-hACE2 mice, while viral shedding profiles and viral titers in lungs were similar between the K18-hACE2 and the C57BL/6J mice. These data suggest B.1.1.529 virus adaptation to a new host and shows that asymptomatic carriers can accumulate and shed virus. Next, we show how B.1.617.2, WA1 and BA5.2/Omicron have similar viral replication kinetics, pathogenicity, and viral shedding profiles in hamsters, demonstrating that the increased pathogenicity of B.1.617.2 observed in mice is host-dependent. Overall, these findings suggest that small animal models are useful to parallel human clinical data, but the experimental design places an important role in interpreting the data. Importance: There is a need to investigate SARS-CoV-2 variant phenotypes in different animal models due to the lack of reproducible outcomes when translating experiments to the human population. Our findings highlight the correlation of clinically relevant SARS-CoV-2 variants in animal models with human infections. Experimental design and understanding of correct animal models are essential to interpreting data to develop antivirals, vaccines, and other therapeutic compounds against COVID-19.

The MNU Plus Testosterone Rat Model of Prostate Carcinogenesis.

Animal models of prostate cancer are essential to identify chemopreventive treatments against this major male malignancy. The N-methyl-N-nitrosourea (MNU) plus testosterone rat model of prostate carcinogenesis is a reliable animal model that recapitulates human prostate cancer in many respects and has been used extensively in chemoprevention studies with good predictive value for the results of human clinical trials. The objective of this article is to describe the induction protocol of this model, demonstrate its robustness and reproducibility over time and across rat strains, provide diagnostic criteria for the identification of prostate lesions, and present the current tumor induction protocol so that others can use this model in a reliable manner. The majority of accessory sex gland tumors in this model are adenocarcinomas originating in the anterior and dorsolateral prostate that metastasize to lungs and abdominal structures. The rat strain used is of critical importance, with the commercially available Wistar WU and Fischer F344 strains yielding the highest tumor incidences. Low dose, long-term testosterone treatment is essential for a high tumor incidence, but in advanced stage, large adenocarcinomas do not appear to be androgen dependent. This rat model is a robust and reproducible prostate cancer animal model of human prostate cancer.

A tandem-repeat dimeric RBD protein-based covid-19 vaccine zf2001 protects mice and nonhuman primates

ABSTRACT Safe, efficacious, and deployable vaccines are urgently needed to control COVID-19 in the large-scale vaccination campaigns. We report here the preclinical studies of an approved protein subunit vaccine against COVID-19, ZF2001, which contains tandem-repeat dimeric receptor-binding domain (RBD) protein with alum-based adjuvant. We assessed vaccine immunogenicity and efficacy in both mice and non-human primates (NHPs). ZF2001 induced high levels of RBD-binding and SARS-CoV-2 neutralizing antibody in both mice and non-human primates, and elicited balanced TH1/TH2 cellular responses in NHPs. Two doses of ZF2001 protected Ad-hACE2-transduced mice against SARS-CoV-2 infection, as detected by reduced viral RNA and relieved lung injuries. In NHPs, vaccination of either 25 μg or 50 μg ZF2001 prevented infection with SARS-CoV-2 in lung, trachea, and bronchi, with milder lung lesions. No evidence of disease enhancement was observed in both animal models. ZF2001 has been approved for emergency use in China, Uzbekistan, Indonesia, and Columbia. The high safety, immunogenicity, and protection efficacy in both mice and NHPs found in this preclinical study was consistent with the results in human clinical trials.

Cytokines: Signalling Improved Immunotherapy?

Immune checkpoint immunotherapies (ICI) are now approved for over 20 types of cancer and there are almost 6000 ongoing clinical trials investigating immuno-modulators as cancer therapies. This review investigated the effect of monoclonal antibody-based immune checkpoint immunotherapies when combined with cytokine therapy. We reviewed published clinical trial results from 2005 to 2020 for studies that used approved monoclonal antibody ICI in combination with the cytokines. Studies that met the search criteria were assessed for treatment efficacy and immunological changes associated with treatment. ICI often fails to result in improved clinical outcomes for patients and lasting protection from cancer recurrence. The use of pro-inflammatory cytokines alongside ICI has been shown to enhance the efficacy of these therapies in vitro and in animal studies. However, the results in human clinical trials are less clear and many clinical trials do not publish results at the end of the trial. A deeper understanding of the molecular interactions between cytokines, tumors, and immune cells is needed to improve overall ICI outcomes and design combination trials. Critical examination of the design and characteristics of previous clinical trials can provide insight into the lack of effective clinical translation for many immunotherapeutic drugs.

Abstract 3067: Exploring strategies to modulate mitochondrial metabolism to alleviate tumor hypoxia

Abstract Radiation therapy is a standard type of treatment modality used as a part of curative or palliative treatment in more than 50% of all cancer patients. However, tumor hypoxia reduces the effectiveness of radiation therapy by limiting the biologically effective dose. Here, we explore and compare strategies to alleviate hypoxia by modifying the oxygen supply or demand within mouse tumor models. We used pODD-Luc, a dynamic in vivo luciferase reporter system that monitors relative levels of tumor hypoxia in real time. We show that in mouse tumor models, contrary to the reported results of human clinical trials, acute manipulation of systemic oxygen delivery significantly reduces the level of hypoxia. We then examined pharmacological manipulation of oxygen demand, which is an emerging trend in therapeutic efforts to sensitize tumors to anti-cancer therapy. Mitochondrial oxygen consumption (OCR) constitutes more than 90% of cellular oxygen demand by coupling carbon source oxidation with ATP generation in a series of redox reactions transferring electrons from reduced cofactors to molecular oxygen. Mechanistically, a decrease in mitochondrial OCR would lead to increased oxygen availability within the tumor, allowing initially hypoxic areas to become re-oxygenated. We found that strategies that directly stimulate mitochondrial OCR exacerbate levels of hypoxia while OCR suppression in turn promotes tumor re-oxygenation. We have previously shown that papaverine, an FDA-approved phosphodiesterase 10A (PDE10A) inhibitor effectively reduces hypoxic tumor fractions in vivo by an off-target effect that inhibits mitochondrial complex I. Here we show that its novel derivative SMV-32 that acts as complex I inhibitor with reduced PDE10A effect mediates superior OCR inhibition in both orthotopic and heterotopic mouse tumor models. These findings further establish the direct impact of OCR manipulation on tumor hypoxia and support the role of mitochondrial metabolism as an attractive target to alleviate tumor hypoxia and overcome treatment resistance. Citation Format: Martin Benej, Jinghai Wu, McKenzie Kreamer, Sandip Vibhute, Ioanna Papandreou, Nicholas C. Denko. Exploring strategies to modulate mitochondrial metabolism to alleviate tumor hypoxia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 3067.

Antigen-specific tolerance approach for rheumatoid arthritis: Past, present and future.

Rheumatoid arthritis is a chronic systemic autoimmune disease, affecting mainly the joints. It is caused by an adaptive immune reaction against self-antigens, leading to the over production of inflammatory cytokines and autoantibodies, mainly mediated by autoreactive CD4+ T cells and pathological B cell clones. The treatment options currently available rely on palliative global immunosuppression and do not restore tolerance to self-components. Here, we review antigen-specific tolerance approaches that have been developed to inhibit or delete autoreactive clones, while maintaining a potent immune system for rheumatoid arthritis. The first attempts relied on the oral ingestion of self-reactive peptides, with lukewarm results in human clinical trials. To enhance treatment efficacy, self-peptides have been engineered and combined with immunosuppressive molecules. In addition, several routes of delivery have been tested, in particular, nanoparticles carrying self-antigens and immunomodulatory molecules. More recently, transfer of immune cells, such as tolerogenic dendritic cells or regulatory T cells, has been considered to restore tolerance. Although promising results have been obtained in mouse models, the translation to humans remains highly challenging, mainly because the disease is already well developed when treatments start and because patient's specific self-antigens are often unknown. Nevertheless, these approaches hold great promises for long-term RA treatment.

Abstract 14859: Mesenchymal Stem Cells Rescue Patient-Specific Cardiomyocyte Viability and Function Following Doxorubicin Injury via Microvesicle Mediated Mitochondrial Transfer to Recapitulate Human Clinical Trial Results

Introduction: Anthracyclines are effective chemotherapeutic agents associated with cardiac toxicity. Anthracycline induced cardiomyopathy (AIC) carries a mortality of 20% at four years. Effective therapies for AIC have not been established. The NIH-sponsored Stem Cell Injection for Cancer Survivors (SENECA) Trial examined the role of allogeneic mesenchymal stem cells (MSC) to treat AIC. To predict the efficacy of MSC in the SENECA patients, we performed an in vitro clinical trial to study the restorative effects of MSC on patient-specific iPSC-derived cardiomyocytes (iCM) by assessing the effects in vitro following doxorubicin (dox) exposure. Hypothesis: MSC secretome will rescue SENECA Trial patient-specific iCM from dox injury. Methods and Results: We generated three SENECA patient-specific iPSC lines. In vitro iCM dox sensitivity was shown to be comparable to published values. iCM were cultured in 1μM dox for 24hrs, treated with MSC or MSC-secretome, and assessed for viability and apoptosis. Co-culture of MSC with iCM using a 1μm trans-well system improved iCM viability by 43% (p-value < 0.005) and reduced apoptosis (p-value = 0.013). To better define the paracrine mechanism, MSC-secretome was divided into microvesicles >200nm (MV) and exosomes <200nm (Ex) using a novel filtration system. MV recapitulated the effect of co-culture, improving iCM viability by 87.8% (p-value = 0.006) and reducing apoptosis by 60% (p-value = 0.013). Treatment with Ex had no effect. MV restore contractility and calcium transients in the dox-injured iCM. MV were found to contain mitochondria (MT), which are taken up by iCM. Treated iCM demonstrate increased MT-copy number and augmented MT-biogenesis. Inhibition of MT function in MV attenuated therapeutic efficacy. We were unblinded to SENECA outcomes. In our cohort, the MSC-treated patient improved across all endpoints while placebo treated patients did not consistent with our in vitro findings. Conclusion: Allogeneic MSC attenuate apoptosis and restore contractility following dox injury in patient-specific iCM. MV and MT-transfer appear to be the putative mechanism. Our findings correlate with the SENECA results, demonstrating proof-of-concept that iPSC-derivatives can be used to predict trial outcomes.

Ayurveda: (W)here is the evidence

It is common to hear a general statement that Ayurveda lacks scientific evidence. By scientific evidence, it is commonly referred to results of human clinical trials undertaken adoring those applied to pharmaceuticals, involving randomized controlled trials (RCT), either a placebo or active controlled. This paper explores the actual situation related to practice of Ayurveda, use of medicines, application of therapies, and the individual dravyas (ingredients). It gives few examples and availability of large body of scientific data in this area. The study, however, does not discuss the reasons and problems of conducting RCTs.

CpG Oligonucleotides as Vaccine Adjuvants.

CpG Oligonucleotides (ODN) are immunomodulatory synthetic oligonucleotides specifically designed to stimulate Toll-like receptor 9. TLR9 is expressed on human plasmacytoid dendritic cells and B cells and triggers an innate immune response characterized by the production of Th1 and pro-inflammatory cytokines. This chapter reviews recent progress in understanding the mechanism of action of CpG ODN and provides an overview of human clinical trial results using CpG ODN to improve vaccines for the prevention/treatment of cancer, allergy, and infectious disease.

Diagnostic and therapeutic applications of genomic medicine in progressive, late-onset, nonsyndromic sensorineural hearing loss.

The progressive, late-onset, nonsyndromic, sensorineural hearing loss (PNSHL) is the most common cause of sensory impairment globally, with presbycusis affecting greater than a third of individuals over the age of 65. The etiology underlying PNSHL include presbycusis, noise-induced hearing loss, drug ototoxicity, and delayed-onset autosomal dominant hearing loss (AD PNSHL). The objective of this article is to discuss the potential diagnostic and therapeutic applications of genomic medicine in PNSHL. Genomic factors contribute greatly to PNSHL. The heritability of presbycusis ranges from 25 to 75%. Current therapies for PNSHL range from sound amplification to cochlear implantation (CI). PNSHL is an excellent candidate for genomic medicine approaches as it is common, has well-described pathophysiology, has a wide time window for treatment, and is amenable to local gene therapy by currently utilized procedural approaches. AD PNSHL is especially suited to genomic medicine approaches that can disrupt the expression of an aberrant protein product. Gene therapy is emerging as a potential therapeutic strategy for the treatment of PNSHL. Viral gene delivery approaches have demonstrated promising results in human clinical trials for two inherited causes of blindness and are being used for PNSHL in animal models and a human trial. Non-viral gene therapy approaches are useful in situations where a transient biologic effect is needed or for delivery of genome editing reagents (such as CRISPR/Cas9) into the inner ear. Many gene therapy modalities that have proven efficacious in animal trials have potential to delay or prevent PNSHL in humans. The development of new treatment modalities for PNSHL will lead to improved quality of life of many affected individuals and their families.

The use of curcumin as an effective adjuvant to cancer therapy: A short review.

Turmeric (Curcuma longa) is a popular spice that has been used in Ayurvedic medicine for its ability to treat various common ailments. There have been statistical correlations between turmeric consumption and lower incidences of cancer development, prompting research into its primary component curcumin. Several in vitro and in vivo studies over the last decade into cancer treatment have provided experimental evidence that curcumin contains antiproliferative, antiangiogenic, and apoptotic properties. The results of human clinical trials however, have proven mostly to be inconclusive. This short review provides an insight into the properties of curcumin including its bioavailability, biological activity, and potential usage in clinical trials as a chemotherapeutic drug.

Central Sensitization, N-methyl-D-aspartate Receptors, and Human Experimental Pain Models: Bridging the Gap between Target Discovery and Drug Development.

Central Sensitization, N-methyl-D-aspartate Receptors, and Human Experimental Pain Models: Bridging the Gap between Target Discovery and Drug Development.

Nutrition, osteoarthritis and cartilage metabolism.

Osteoarthritis (OA) is a degenerative joint disease and a leading cause of adult disability. There is no cure for OA and there is no effective treatment to stop its progression. Current pharmacologic treatments such as analgesics and non-steroidal anti-inflammatory drugs may improve the pain and offer some relief but they do not affect the progression of the disease. The chronic intake of these drugs may result in severe adverse events. The aim of this review is to revise the effects of nutrition on cartilage metabolism and OA progression. A systematic literature search was performed including those related to macro- and micro-nutrients' actions on cartilage and OA outcome. We selected peer-reviewed articles reporting the results of human clinical trials. Glucosamine and chondroitin sulfate have shown to delay OA knee progression in several clinical trials. The effectiveness of some products considered nutraceuticals has been widely reviewed in the literature. This article presents a general description of the effectiveness and mechanism of action of nutrients, vitamins, antioxidants and other natural components considered as part of the normal diet. Many in vitro studies indicate the efficacy of specific nutrients in cartilage metabolism and its involvement in OA. However, rigorous clinical studies needed to evaluate the efficacy of these compounds in humans are still missing. The influence of nutrients and diet on the metabolism of cartilage and OA could represent a long-term coadjuvant alternative in the management of patients with OA. Effects of diet modifications on lipid and cholesterol profiles, adequate vitamin levels and weight reduction in obese patients could influence the course of the disease. This review demonstrates that nutrition can improve the symptoms of OA. Glucosamine and chondroitin sulfate have shown robustly to delay the progression of knee OA in several well-designed studies, however more controlled clinical trials are needed to conclude that nutritional changes slow down the progression of the disease.

Cachexia and Sarcopenia in Companion Animals: An Under‐Utilized Natural Animal Model of Human Disease

AbstractWhile laboratory small animal models of cachexia and sarcopenia are well‐suited and critical for studying mechanisms and early pre‐clinical phases for potential treatments, they are not similar enough to the human conditions to always be good predictors for results in human clinical trials. As a result, translational failures can occur when large‐scale human clinical trials are conducted on drugs, even when they appear promising in pre‐clinical studies in rodent models. What is needed is a way to more efficiently and successfully translate information gained from basic science and rodent research into human clinical trials that produce effective approved drugs. Naturally‐occurring cachexia and sarcopenia in companion animals is a more representative model of human disease that can serve as a stepping stone between basic science and human clinical trials. Many of the common diseases of humans also affect companion animals, particularly pet dogs and cats. Pet dogs and cats commonly develop heart failure, cancer, and kidney disease, as well as acute trauma or illness. The population of elderly companion animals also is increasing as pets' lifespans have become longer. As a result, both cachexia and sarcopenia are very common in companion animals. Studying these conditions in dogs and cats – either in colonies or in animal clinical trials ‐ can help to identify successful treatments that can benefit both humans and companion animals.

Effect of Conjugated Linoleic Acid on Leptin Level: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

The results of human clinical trials examining the effects of conjugated linoleic acid (CLA) on leptin concentration are inconsistent. Our objective was to elucidate the role of conjugated linoleic acid supplementation on leptin through a systematic review and a meta-analysis of available randomized placebo-controlled trials (RCTs). We searched the PubMed, SCOPUS, and ISI web of science up to February2017, in English, to identify RCTs investigating the effect of CLA supplements on plasma leptin concentrations. Weighted mean differences (WMDs) and their respective 95% confidence intervals (CIs) were calculated to assess the efficacy of CLA on leptin concentration by using random effects. Statistical heterogeneity, study quality, meta-regression and publication bias were used based on standard methods. Nineteen RCTs (comprising 26 treatment arms) with 1045 subjects were included in this meta-analysis. Random-effect meta-analysis found a slight but not significant reduction in plasma leptin concentrations (WMD: -0.38 ng/ml, 95% CI: -1.08, 0.32, p=0.286); I2=53.24%, p=0.001), following CLA supplementation. The pooled effect size was robust and remained non-significant in the leave-one-out sensitivity analysis. Subgroup analysis based on BMI status showed that the CLA supplementation significantly reduces leptin when used for obese subjects (WMD: -1.47 ng/ml, 95% CI: -2.15, -0.79, p<0.001) and in the subset of trials lasting<24 weeks of duration (WMD: -0.76 ng/ml, 95% CI: -1.40, -0.12, p=0.019). CLA supplementation might moderately decrease circulatory leptin levels only among obese adults for shorter than 24 weeks. Additional high-quality studies are needed to replicate our results.

Flaxseed supplementation on glucose control and insulin sensitivity: a systematic review and meta-analysis of 25 randomized, placebo-controlled trials.

The results of human clinical trials investigating the effects of flaxseed on glucose control and insulin sensitivity are inconsistent. The present study aimed to systematically review and analyze randomized controlled trials assessing the effects of flaxseed consumption on glycemic control. PubMed, Medline via Ovid, SCOPUS, EMBASE, and ISI Web of Sciences databases were searched up to November 2016. Clinical trials in which flaxseed or its products were administered as an intervention were included. The outcomes were fasting blood glucose, insulin concentration, insulin resistance (HOMA-IR), insulin sensitivity (QUIKI), and hemoglobin A1c (HbA1c). A total of 25 randomized clinical trials (30 treatment arms) were included. Meta-analysis suggested a significant association between flaxseed supplementation and a reduction in blood glucose (weighted mean difference [WMD], -2.94 mg/dL; 95%CI, -5.31 to - 0.56; P = 0.015), insulin levels (WMD, -7.32 pmol/L; 95%CI, -11.66 to -2.97; P = 0.001), and HOMA-IR index (WMD, -0.49; 95%CI,: -0.78 to - 0.20; P = 0.001) and an increase in QUIKI index (WMD, 0.019; 95%CI, 0.008-0.031; P = 0.001). No significant effect on HbA1c (WMD, -0.045%; 95%CI, -0.16 to - 0.07; P = 0.468) was found. In subgroup analysis, a significant reduction in blood glucose, insulin, and HOMA-IR and a significant increase in QUIKI were found only in studies using whole flaxseed but not flaxseed oil and lignan extract. Furthermore, a significant reduction was observed in insulin levels and insulin sensitivity indexes only in the subset of trials lasting ≥12 weeks. Whole flaxseed, but not flaxseed oil and lignan extract, has significant effects on improving glycemic control. Further studies are needed to determine the benefits of flaxseed on glycemic parameters.