Effects of melamine and cyanuric acid on renal function and structure in rats

Melamine has been used to increase the amount of measurable nitrogen which is a component of protein. The renal toxicity of melamine has been reported in infants and animals that consumed a mixture of melamine in their food products. This study aimed to investigate the effects of melamine on rat renal function using clearance and histological techniques. Animals were divided into 3 groups: vehicle control, 400 mg/kg melamine and mixture of 400 mg/kg melamine and 400 mg/kg cyanuric acid (p.o., daily for three days). The results showed that blood urea nitrogen level significantly increased in the rats treated with the mixture of melamine and cyanuric acid. The urine flow rate, glomerular filtration rate, renal plasma flow and urinary sodium and potassium excretion rate significantly decreased when compared to vehicle control. These results suggested both glomeruli and renal tubules of rats treated with mixture of melamine and cyanuric acid were damaged. Histological study also confirmed these findings and showed significant glomerular atrophy and dilated renal tubules. Numerous clear brownish-yellow crystals were also found in the distal tubule, collecting tubule and papillary duct. However, rats solely treated with melamine showed no significant difference in renal function or structures

Daily Step Count and its Association with Arterial Stiffness Parameters in Older Adults

Background Daily step count is a simple parameter for assessing physical activity. However, the potential advantages of setting daily step goals below the traditional 10,000-step threshold remain unclear. The cross-sectional study aimed to determine the relationship between daily step counts and arterial stiffness outcomes in older individuals. Methods Forty-eight older adults recorded their daily step counts over a 7-day period using a pedometer. The participants were classified into two groups based on their daily step count: Group 1 (n = 28) consisted of individuals taking fewer than 5000 steps per day, while Group 2 (n = 20) included those who recorded 5,000 to 9,999 steps per day. To evaluate arterial stiffness parameters, we measured pulse wave velocity (PWV), cardio-ankle vascular index (CAVI), and ankle-brachial index (ABI). Hemodynamic and biochemical parameters were also determined. Results Participants who accumulated fewer daily steps exhibited higher PWV compared to each group. An inverse association was observed between average steps per day and PWV. However, no significant differences were found between daily step counts and CAVI or ABI. Conclusions As individuals increase their daily step count, they may experience a reduction in arterial stiffness. Consequently, the assessment of daily steps has benefits for enhancing vascular health and overall well-being among older individuals

การกระตุ้นการแสดงออกของยีนไซโตไคน์และคีโมไคน์ในเซลล์เยื่อบุผิวหลอดลมย่อยทางเดินหายใจของคนไทยไวรัสไข้หวัดนกสายพันธุ์ H5N1

Thesis (M.Sc. (Physiology))--Prince of Songkla University, 201

Impact of Fasting Blood Glucose Levels on Blood Pressure Parameters among Older Adults with Prediabetes

Prediabetes mellitus (pre-DM) is defined as blood glucose levels higher than normal but lower than the threshold for diabetes mellitus (DM) diagnosis. Four-limb blood pressure (BP) differences can help identify a significant risk for cardiovascular diseases (CVDs). The current study aimed to determine the importance of BP and the ankle-brachial index (ABI) between two patient groups and the association between fasting blood glucose (FBG) levels and four-limb BP, ABI, interarm BP difference (IAD), and interleg BP difference (ILD). Moreover, the effect of cardiovascular risk factors on the development of pre-DM among older adults was evaluated. The participants were divided into the normal fasting glucose (NFG) and impaired fasting glucose (IFG) groups. Data on physical characteristics, lipid profiles, four-limb BP, ABI, IAD, ILD, and cardiovascular risk factors were assessed. The IFG group had a significantly higher systolic blood pressure (SBP) and pulse pressure than the NFG group (p < 0.05). SBP was significantly positively correlated with FBG levels (p < 0.05). The IFG group had a lower ABI than the NFG group (p < 0.05). However, there was no significant difference in terms of IAD and ILD between the two groups. Furthermore, hypertension (HT), metabolic syndrome (MetS), and dyslipidemia were significantly correlated with a high prevalence of prediabetes (p < 0.05). Individuals with prediabetes had a higher BP than those with normoglycemia. Prediabetes was correlated with HT, MetS, and dyslipidemia

Sargassum plagiophyllum Extract Enhances Colonic Functions and Modulates Gut Microbiota in Constipated Mice

Constipation is a symptom that is widely found in the world&rsquo;s population. Various dietary supplementations are used to relieve and prevent constipation. Seaweed is widely used for its health benefits. In this study, we aimed to investigate the effects of Sargassum plagiophyllum extract (SPE) on functions of the gastrointestinal tract and gut microbiota. The results show that SPE pretreatment increased the frequency of gut contraction, leading to reduce gut transit time. SPE pretreatment also significantly increased the secretion of Cl&minus; and reduced Na+ absorption, increasing fecal water content in constipated mice (p &lt; 0.05). In addition, the Bifidobacteria population in cecal contents was significantly higher in constipated mice pretreated with 500 mg/kg SPE for 14 days than in untreated constipated mice (p &lt; 0.05). Our findings suggest that SPE can prevent constipation in loperamide-induced mice. This study may be useful for the development of human food supplements from S. plagiophyllum, which prevent constipation

P2Y₆ receptors are involved in mediating the effect of inactivated avian influenza virus H5N1 on IL-6 & CXCL8 mRNA expression in respiratory epithelium

<div><p>One of the key pathophysiologies of H5N1 infection is excessive proinflammatory cytokine response (cytokine storm) characterized by increases in IFN-β, TNF-α, IL-6, CXCL10, CCL4, CCL2 and CCL5 in the respiratory tract. H5N1-induced cytokine release can occur via an infection-independent mechanism, however, detail of the cellular signaling involved is poorly understood. To elucidate this mechanism, the effect of inactivated (β-propiolactone-treated) H5N1 on the cytokine and chemokine mRNA expression in 16HBE14o- human respiratory epithelial cells was investigated. We found that the inactivated-H5N1 increased mRNA for IL-6 and CXCL8 but not TNF-α, CCL5 or CXCL10. This effect of the inactivated-H5N1 was inhibited by sialic acid receptor inhibitor (α-2,3 sialidase), adenosine diphosphatase (apyrase), P2Y receptor (P2YR) inhibitor (suramin), P2Y₆R antagonist (MRS2578), phospholipase C inhibitor (U73122), protein kinase C inhibitors (BIM and Gö6976) and cell-permeant Ca²⁺ chelator (BAPTA-AM). Inhibitors of MAPK signaling, including of ERK1/2 (PD98059), p38 MAPK (SB203580) and JNK (SP600125) significantly suppressed the inactivated-H5N1-induced mRNA expression of CXCL8. On the other hand, the inactivated-H5N1-induced mRNA expression of IL-6 was inhibited by SB203580, but not PD98059 or SP600125, whereas SN-50, an inhibitor of NF-κB, inhibited the effect of virus on mRNA expression of both of IL-6 and CXCL8. Taken together, our data suggest that, without infection, inactivated-H5N1 induces mRNA expression of IL-6 and CXCL8 by a mechanism, or mechanisms, requiring interaction between viral hemagglutinin and α-2,3 sialic acid receptors at the cell membrane of host cells, and involves activation of P2Y₆ purinergic receptors.</p></div