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Cyanobacteria play a crucial role in global carbon and nitrogen cycles through photosynthesis, making them valuable subjects for understanding the factors influencing their light utilization efficiency. Photosynthetic microorganisms offer a promising avenue for sustainable energy conversion in the field of photovoltaics. It was demonstrated before that application of an external electric field to the microbial biofilm or cell improves electron transfer kinetics and, consequently, efficiency of power generation. We have integrated live cyanobacterial cultures into photovoltaic devices by embedding Limnospira indica PCC 8005 cyanobacteria in agar and PEDOT:PSS matrices on the surface of boron-doped diamond electrodes. We have subjected them to varying external polarizations while simultaneously measuring current response and photosynthetic performance. For the latter, we employed Pulse-Amplitude-Modulation (PAM) fluorometry as a non-invasive and real-time monitoring tool. Our study demonstrates an improved light utilization efficiency for L. indica PCC 8005 when immobilized in a conductive matrix, particularly so for low-intensity light. Simultaneously, the impact of electrical polarization as an environmental factor influencing the photosynthetic apparatus diminishes as matrix conductivity increases. This results in only a slight decrease in light utilization efficiency for the illuminated sample compared to the dark-adapted state., (© 2024. The Author(s).)

We present the change of light absorption of cyanobacteria in response to externally applied electrical polarization. Specifically, we studied the relation between electrical polarization and changes in light absorbance for a biophotoelectrode assembly comprising boron-doped diamond as semiconducting electrode and live Limnospira indica PCC 8005 trichomes embedded in either polysaccharide (agar) or conductive conjugated polymer (PEDOT-PSS) matrices. Our study involves the monitoring of cyanobacterial absorbance and the measurement of photocurrents at varying wavelengths of illumination for switched electric fields, i.e., using the bioelectrode either as an anode or as cathode. We observed changes in the absorbance characteristics, indicating a direct causal relationship between electrical polarization and absorbing properties of L. indica . Our finding opens up a potential avenue for optimization of the performance of biophotovoltaic devices through controlled polarization. Furthermore, our results provide fundamental insights into the wavelength-dependent behavior of a bio photovoltaic system using live cyanobacteria., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Background: Platelet hyperactivity has a crucial role in initiating vascular thrombosis and subsequent cardiovascular disease (CVD)., Objective: This study aimed to assess the effect of anthocyanins (AC) on platelet aggregation and activation and lipid profile., Study Design: A total of 26 healthy participants consumed 320 mg of AC/day in the form of Medox® capsules for 28 days., Setting: This study was conducted in the laboratories of the School of Medical Sciences, Griffith University, Gold Coast, Australia., Participants: A total of 26 randomly recruited healthy 25- to 75-year-old participants completed this study., Primary Outcome Measures: Fasting blood samples were collected pre- and post-the intervention period to perform platelet activation studies by measuring platelet surface marker expression of CD41a and P-selectin, and platelet-monocyte aggregates in adenosine diphosphate (ADP) stimulated platelets. Platelet aggregation studies were performed by stimulating platelets with various agonists such as ADP, collagen and arachidonic acid. Full blood examination, coagulation and biochemistry profile analyses were also performed pre- and post-intervention. Flow cytometric analysis showed a significant effect of AC on the expression of P-selectin as measured by the platelet surface expression of CD62p., Results: There was a significant reduction of ADP-stimulated platelet aggregation. Hematologic analysis showed a significant reduction of mean platelet volume, mean cell hemoglobin, and mean cell hemoglobin concentration. Coagulation analysis demonstrated significant attenuation of fibrinogen level in the blood., Conclusion: This study showed inhibition of platelet activity, platelet aggregation and mean platelet volume (MPV). These results suggest that AC has a positive impact on attenuating platelet activity, which might minimize thrombotic risk.

Objective: The present research aimed to investigate the anti-inflammatory potential of dietary anthocyanin (ACN) in type 2 diabetic (T2D), T2D-at-risk and healthy individuals. Furthermore, dietary inflammatory index (DII) was used to study the association of diet with biomarkers of inflammation., Research Methods: An open-label clinical trial was conducted at Griffith University investigating the efficacy of 320 mg ACN supplementation per day over the course of 4 weeks. Diabetes-associated inflammatory biomarkers and relevant biochemical and physical parameters were tested pre-and post-intervention, and participants' dietary inflammatory potential was estimated., Results: A significant reduction in the pro-inflammatory biomarkers' interleukin-6, interleukin-18, and tumour necrosis factor-α was observed in the T2D group. In addition, some, but not all, biochemical parameters including fasting blood glucose, low-density lipoprotein cholesterol and uric acid were significantly improved in T2D-at-risk group. Moreover, a significant difference was detected between the DII scores of the healthy and T2D groups. DII score for the T2D group was consistent with an anti-inflammatory diet., Conclusion: Anti-inflammatory potential of dietary ACN in T2D participants was evidenced in the present study. Although, anti-inflammatory dietary patterns of T2D participants may have accelerated the anti-inflammatory effect of the ACN capsules supplemented in this trial.

Background: Alcohol exposure alters the expression of a large number of genes, resulting in neuronal adaptions and neuronal loss, but the underlying mechanisms are largely unknown. miRNAs are gene repressors that are abundant in the brain. A recent study identified ~ 35 miRNAs that are up-regulated in the prefrontal cortex of human alcoholics and predicted to target genes that are down-regulated in the same region. Although interactions between alcohol-responsive miRNAs and their target genes have been predicted, few studies have validated these predictions., Methods: We measured the expression of GABA A α5 mRNA in the prefrontal and motor cortices of human alcoholics and matched controls using real-time PCR. The expression of miR-203 was measured in a subset of these cases. The predicted interaction of miR-203 and GABRA5 was validated for miR-203 using a luciferase reporter assay., Results: In both frontal and motor cortices, the expression of GABA A α5 was significantly lower in cirrhotic alcoholics compared with controls. Further, the pattern of expression between the groups was significantly different between males and females. The expression of miR-203 was higher in the prefrontal cortex of cirrhotic alcoholics compared with controls and uncomplicated alcoholics. These differences were particularly marked in female cases. Cotransfection of GABRA5 with miR-203 in HEK293T cells reduced luciferase reporter activity., Conclusion: There are sex differences in the expression of GABA A α5 and miR-203 in the brain of human alcoholics which are particularly marked in alcoholics with cirrhosis of the liver. Further, miR-203 may mediate the changes in expression of this GABA A receptor isoform that is brought about by alcohol exposure., (© 2019 by the Research Society on Alcoholism.)

Background: Increased platelet activity plays a significant role in the development of arterial thrombosis and cardiovascular disease (CVD). Natural antioxidants including anthocyanin (AC) have gained considerable interest due to their hypothesized antithrombotic potential., Primary Study Objective: Our study aimed to examine the in vitro effect of AC compounds on platelet activation and aggregation., Methods: Fasting blood samples were collected from healthy volunteers (n = 13). A full blood examination was done to exclude any abnormal specimen. Flow cytometer assessed platelet activity by recording platelet surface markers expression of P-selectin (CD62P) and PAC-1. Platelet aggregation studies were performed by stimulating platelets using three different agonists adenosine diphosphate (ADP), collagen and arachidonic acid (AA)., Setting: The study was done in the school of Medical Sciences, Griffith University., Participants: Thirteen healthy adult participants were involved for blood collection., Intervention: AC was prepared using hemicellulose capsules sourced from Bilberries and Black Currants., Results: Anthocyanin (50 mg/L) significantly inhibited AA-induced platelet aggregation. Expression of P-selectin was significantly suppressed by 50 mg/L AC as measured by flow cytometer., Conclusions: AC attenuates platelet function by suppressing P-selectin expression and influencing Thromboxane A2 pathway (AA stimulation). These results provide further evidence for the effect of AC and the possible mechanism by which AC reduces platelet aggregation and activation. This study supports future human intervention trials to show that AC may act as a complement to other antiplatelet agents in reducing the risk of thrombosis.

Context • Type 2 diabetes mellitus is an independent precipitating factor for cardiovascular disease (CVD). Heart disease is one of the leading causes of mortality in patients with diabetes, mainly due to macrovascular complications, such as atherosclerosis. Although aspirin is a frequently used therapy for the inhibition of platelet hyperactivity, many studies suggest that aspirin resistance is rising. Objective • The study intended to investigate the benefits of anthocyanin (AC) as an antioxidant with inhibitory effects on platelets and, consequently, its potential usefulness as complementary antiplatelet therapy to attenuate the negative effects of atherosclerosis and CVD in patients with diabetes. Design • The research team performed a literature review. The team conducted a database search from 2007 to 2017 using Library of Congress, LISTA, PubMed, and Web of Science Core Collection databases, using the following keywords: anthocyanins, platelet, cardiovascular disease, and diabetes. Setting • The study took place at the School of Medical Sciences at Griffith University's Gold Coast campus (Southport, Australia). Results • Platelets have a major pathophysiological role of atherosclerosis and consequently CVD in diabetes. Antiplatelet drugs have a potent inhibitory effect of thrombotic and CVD risks in diabetes. Dietary antioxidants including ACs have a potential platelet inhibitory effect. Hence, ACs may act as complementary therapy to reduce CVD in diabetes. Conclusions • Although antiplatelet drugs such as aspirin provide significant action in the management of CVD, aspirin has limited benefits in diabetes. An AC antioxidant has a potential effect as an antiplatelet agent that subsequently can prevent atherosclerosis and CVD and, therefore, AC may be an alternative to other antiplatelet drugs such as aspirin. However, more interventional studies and large-scale clinical trials are necessary to prove the efficiency of AC as an alternative to other platelet-inhibitory drugs.

Purpose: High fasting blood glucose (FBG) can lead to chronic diseases such as diabetes mellitus, cardiovascular and kidney diseases. Consuming probiotics or synbiotics may improve FBG. A systematic review and meta-analysis of controlled trials was conducted to clarify the effect of probiotic and synbiotic consumption on FBG levels., Methods: PubMed, Scopus, Cochrane Library, and Cumulative Index to Nursing and Allied Health Literature databases were searched for relevant studies based on eligibility criteria. Randomized or non-randomized controlled trials which investigated the efficacy of probiotics or synbiotics on the FBG of adults were included. Studies were excluded if they were review articles and study protocols, or if the supplement dosage was not clearly mentioned., Results: A total of fourteen studies (eighteen trials) were included in the analysis. Random-effects meta-analyses were conducted for the mean difference in FBG. Overall reduction in FBG observed from consumption of probiotics and synbiotics was borderline statistically significant (-0.18 mmol/L 95 % CI -0.37, 0.00; p = 0.05). Neither probiotic nor synbiotic subgroup analysis revealed a significant reduction in FBG. The result of subgroup analysis for baseline FBG level ≥7 mmol/L showed a reduction in FBG of 0.68 mmol/L (-1.07, -0.29; ρ < 0.01), while trials with multiple species of probiotics showed a more pronounced reduction of 0.31 mmol/L (-0.58, -0.03; ρ = 0.03) compared to single species trials., Conclusion: This meta-analysis suggests that probiotic and synbiotic supplementation may be beneficial in lowering FBG in adults with high baseline FBG (≥7 mmol/L) and that multispecies probiotics may have more impact on FBG than single species.

One of the most commonly identified chronic illnesses in many countries is type 2 diabetes mellitus (T2DM). T2DM denotes an independent risk factor for cardiovascular disease (CVD). Heart disease is one of the causes of mortality in patients with diabetes, mainly due to the macrovascular complications. One of these macrovascular complications in diabetes is atherosclerosis, which involves a complicated pathophysiological process. Besides hyperglycemia, oxidative stress plays a significant role in the pathogenesis of diabetes and its associated risk of CVD. There are many other factors including molecular, metabolic, lipid, fibrinolytic, and platelet function disorders precipitate to thrombotic and CVD risks in T2DM. Also, Platelets have an increased response to procoagulants in patients with diabetes. Platelet hyperactivity, in the presence of oxidative stress, has a major effect on the progression of thrombotic and CVD events. This review will discuss the impact of the above factors and the potential effects of platelet hyperactivity on thrombotic and cardiovascular risks., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Introduction/aim: Interest in the gut-brain axis and emerging evidence that the intestinal microbiota can influence central nervous system function has led to the hypothesis that probiotic supplementation can have a positive effect on mood and psychological symptoms such as depression and anxiety. Although several human clinical trials have investigated this, results have been inconsistent. Therefore, a systematic review and meta-analytic approach was chosen to examine if probiotic consumption has an effect on psychological symptoms., Methods: The online databases PubMed, Scopus, and the Cochrane Library were searched for relevant studies up to July 2016. Those that were randomized and placebo controlled and measured preclinical psychological symptoms of depression, anxiety, and perceived stress in healthy volunteers pre and post supplementation with a probiotic were included. To control for differences in scales of measurement, data were converted to percentage change, and the standardized mean difference between the probiotic and control groups was investigated using Revman software. A random effects model was used for analysis. Heterogeneity was assessed using the I 2 statistic. Quality assessment was undertaken using the Rosendal scale., Results: Seven studies met the inclusion criteria and provided data for nine comparisons. All studies passed the quality analysis. The meta-analysis showed that supplementation with probiotics resulted in a statistically significant improvement in psychological symptoms (standardized mean difference 0.34; 95% confidence interval 0.07-0.61, Z = 2.49) compared with placebo., Conclusion: These results show that probiotic consumption may have a positive effect on psychological symptoms of depression, anxiety, and perceived stress in healthy human volunteers.