Salivary spectral signature using ATR-FTIR spectroscopy in different exercise protocols.

The Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) has been applied to determine salivary biomarkers with high sensitivity and cost-effectiveness. Our study aimed to test the hypothesis that the spectral profile of saliva demonstrates distinct vibrational modes corresponding to different exercise protocols, thereby facilitating exercise monitoring. Saliva samples were collected from trained male subjects at three intervals: pre-exercise, post-exercise, and 3 h post-exercise. The protocols included acute sessions of continuous exercise (CE), high-intensity interval exercise (HIIE), and resistance exercise (RE). ATR-FTIR analysis revealed that salivary biochemical components changed uniquely with each exercise protocol. Specific spectral vibrational modes were identified as potential biomarkers for each exercise type. Notably, the salivary spectrum pattern of CE closely resembled that of HIIE, whereas RE showed minor alterations. Furthermore, we attempted to apply an algorithm capable of distinguishing the spectral range that differentiates the exercise modalities. This pioneering study is the first to compare changes in saliva spectra following different exercise protocols and to suggest spectrum peaks of vibrational modes as markers for specific types of exercises. We emphasize that the spectral wavenumbers identified by FTIR could serve as practical markers in distinguishing between different exercise modalities, with sensitivity, specificity, and accuracy correlating with the metabolic changes induced by exercise. Therefore, this study contributes a panel of ATR-FTIR spectral wavenumbers that can be referenced as a spectral signature capable of distinguishing between resistance and endurance exercises.

Effects of an L-Leucine-Rich Diet on Liver and Kidneys in a Doxorubicin Toxicity Model.

Supplements and diets containing L-leucine, a branched-chain amino acid, have been considered beneficial for controlling oxidative stress and maintaining cardiac tissue in toxicity models using doxorubicin, a drug widely used in cancer treatment. However, there is a lack of studies in the literature that assess the effects of this diet on other organs and tissues, such as the liver and kidneys. Therefore, this study aimed to evaluate the effects of a leucine-rich diet on the liver and kidneys of healthy rats submitted to the doxorubicin toxicity model by analyzing biomarkers of oxidative stress and histological parameters. The animals were divided into four groups: naive, doxorubicin, L-leucine, and doxorubicin + L-leucine, and the diet was standardized with 5% L-leucine and a dose of 7.5 mg/kg of doxorubicin. We evaluated tissue injury parameters and biomarkers of oxidative stress, including enzymes, antioxidant profile, and oxidized molecules, in the liver and kidneys. Although some studies have indicated benefits of a diet rich in L-leucine for the muscle tissue of animals that received doxorubicin, our results showed that the liver was the most affected organ by the L-leucine-rich diet since the diet reduced its antioxidant defenses and increased the deposit of collagen and fat in the hepatic tissue. In the kidneys, the main alteration was the reduction in the number of glomeruli. These results contribute to the scientific literature and encourage further studies to evaluate the effects of an L-leucine-rich diet or its supplementation, alone or combined with doxorubicin using an animal model of cancer. Therefore, our study concludes that the leucine-rich diet itself was harmful and, when co-administered with doxorubicin, was not able to maintain the antioxidant defenses and tissue structure of the evaluated organs.

Increased selenium concentration in the synthesis of CdSe magic-sized quantum dots affects how the brain responds to oxidative stress.

CdSe magic-sized quantum dots (MSQDs) have been widely used as fluorescent probes in biological systems due to their excellent optical properties with a broader fluorescence spectrum and stable luminescence in biological media. However, they can be cytotoxic and alter the redox balance depending on the amounts of Cd2+ adsorbed on their surface. Thus, the present study aimed to evaluate whether increases in selenium concentration in the synthesis of CdSe-MSQDs decrease the oxidative stress caused by Cd2+ -based quantum dots. CdSe-MSQDs synthesized with different concentrations of selenium were investigated against oxidative stress in the brain of chicken embryos by examining total antioxidant capacity, lipid peroxidation, thiol, and glutathione contents, as well as the activities of glutathione peroxidase, superoxide dismutase (SOD), catalase (CAT), and glutathione reductase. In addition, the vascularization of the chorioallantoic membrane (CAM) analysis was performed. Higher selenium concentrations alter the surface defect levels (decrease free Cd2+ ) and controlled the oxidative effects of CdSe-MSQDs by reducing the lipid peroxidation, restoring the glutathione defense system and the antioxidant enzymes SOD and CAT, and maintaining the vascular density of the CAM. The current findings reinforce the study of the effects of the presence of Cd2+ ions on the surface of quantum dots, changing toxicity, and aiming interesting strategies of nanomaterials in biological systems.

Effects of salbutamol and phlorizin on acute pulmonary inflammation and disease severity in experimental sepsis.

Respiratory infection can be exacerbated by the high glucose concentration in the airway surface liquid (ASL). We investigated the effects of salbutamol and phlorizin on the pulmonary function, oxidative stress levels and SGLT1 activity in lung, pulmonary histopathological damages and survival rates of rats with sepsis. Sepsis was induced by cecal ligation and puncture surgery (CLP). Twenty-four hours after surgery, CLP rats were intranasally treated with saline, salbutamol or phlorizin. After 2 hours, animals were anesthetized and sacrificed. Sepsis promoted atelectasis and bronchial inflammation, and led to increased expression of SGLT1 on cytoplasm of pneumocytes. Salbutamol treatment reduced bronchial inflammation and promoted hyperinsuflation in CLP rats. The interferon-ɤ and Interleucin-1ß concentrations in bronchoalveolar lavage (BAL) were closely related to the bronchial inflammation regulation. Salbutamol stimulated SGLT1 in plasma membrane; whereas, phlorizin promoted the increase of SGLT1 in cytoplasm. Phlorizin reduced catalase activity and induced a significant decrease in the survival rate of CLP rats. Taken together, sepsis promoted atelectasis and lung inflammation, which can be associated with SGLT1 inhibition. The loss of function of SGLT1 by phlorizin are related to the augmented disease severity, increased atelectasis, bronchial inflammation and a significant reduction of survival rate of CLP rats. Alternatively salbutamol reduced BAL inflammatory cytokines, bronchial inflammation, atelectasis, and airway damage in sepsis. These data suggest that this selective ß2-adrenergic agonist may protect lung of septic acute effects.

Adaptogenic potential of royal jelly in liver of rats exposed to chronic stress.

Restraint and cold stress increase both corticosterone and glycemia, which lead to oxidative damages in hepatic tissue. This study assessed the effect of royal jelly (RJ) supplementation on the corticosterone level, glycemia, plasma enzymes and hepatic antioxidant system in restraint and cold stressed rats. Wistar rats were allocated into no-stress, stress, no-stress supplemented with RJ and stress supplemented with RJ groups. Initially, RJ (200mg/Kg) was administered for fourteen days and stressed groups were submitted to chronic stress from the seventh day. The results showed that RJ supplementation decreases corticosterone levels and improves glycemia control after stress induction. RJ supplementation also decreased the body weight, AST, ALP and GGT. Moreover, RJ improved total antioxidant capacity, SOD activity and reduced GSH, GR and lipoperoxidation in the liver. Thus, RJ supplementation reestablished the corticosterone levels and the hepatic antioxidant system in stressed rats, indicating an adaptogenic and hepatoprotective potential of RJ.

Royal jelly decreases corticosterone levels and improves the brain antioxidant system in restraint and cold stressed rats.

Restraint and cold stress induces the hypothalamic-pituitary-adrenal (HPA) axis to release corticosterone from the adrenal gland, which can worsen the antioxidant defense system in the central nervous system. Here, we investigated the corticosterone levels and the antioxidant defense system in the cerebellum and brain, as well as in its isolated regions, such as cerebral cortex, striatum and hippocampus of stressed rats supplemented with royal jelly (RJ). Wistar rats were supplemented with RJ for 14days and the stress induction started on the 7th day. Stressed rats increased corticosterone levels, glycemia and lipid peroxidation in the brain and cerebellum, cerebral cortex and hippocampus besides reduced glutathione defense system in the brain and striatum. Rats supplemented with RJ decreased corticosterone, maintained glycemia and decreased lipid peroxidation in the brain, cerebellum, as well as striatum and hippocampus, besides improved glutathione defense system in cerebral cortex and striatum. This study suggests an anti-stress and neuroprotective effect of RJ under stress conditions.

Metformin attenuates the TLR4 inflammatory pathway in skeletal muscle of diabetic rats.

AIMS: Inflammation induced by hyperglycemia triggers the toll-like receptor (TLR) pathway into cells. Our hypothesis was that metformin treatment attenuates the TLR signaling pathways triggered by inflammation in skeletal muscle of hypoinsulinemic/hyperglycemic STZ-induced rats. Thus, we examined TLR signaling under hypoinsulinemia and hyperglycemia conditions and its correlation with insulin resistance in muscle of diabetic rats treated with metformin. METHODS: Ten-day diabetic rats were submitted to 7 days of saline (D group) or metformin (500 mg/kg once per day) (D + M group). The skeletal muscle was collected before the insulin tolerance test. Then, Western blotting analysis of skeletal muscle supernatant was probed with TLR4, TLR2, NF-κB, IκB, p-AMPK and p-JNK. TNF-α and CXCL1/KC content was analyzed by ELISA. RESULTS: Metformin treatment increased whole-body insulin sensitivity. This regulation was accompanied by a parallel change of p-AMPK and by an inverse regulation of TLR4 and NF-κB contents in the soleus muscle (r = 0.7229, r = -0.8344 and r = -0.7289, respectively, Pearson correlation; p < 0.05). Metformin treatment increased IκB content when compared to D rats. In addition, metformin treatment decreased p-JNK independently of TLR2 signal in diabetic rats. CONCLUSION: In summary, the results indicate a relationship between muscular TLR4, p-AMPK and NF-κB content and insulin sensitivity. The study also highlights that in situations of insulin resistance, such as in diabetic subjects, metformin treatment may prevent attenuation of activation of the inflammatory pathway.

Hepatoprotective Properties of a Polyphenol-Enriched Fraction from Annona crassiflora Mart. Fruit Peel against Diabetes-Induced Oxidative and Nitrosative Stress.

A polyphenol-enriched fraction from Annona crassiflora fruit peel (Ac-Pef) containing chlorogenic acid, (epi)catechin, procyanidin B2, and caffeoyl-glucoside was investigated against hepatic oxidative and nitrosative stress in streptozotocin-induced diabetic rats. Serum biochemical parameters, hepatic oxidative and nitrosative status, glutathione defense system analysis, and in silico assessment of absorption, distribution, metabolism, excretion, and toxicity (ADMET) of the main compounds of Ac-Pef were carried out. Ac-Pef treatment during 30 days decreased serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase activities, as well as hepatic lipid peroxidation, protein carbonylation and nitration, inducible nitric oxide synthase level, and activities and expressions of glutathione peroxidase, superoxide dismutase, and catalase. There were increases in antioxidant capacity, glutathione reductase activity, and reduced glutathione level. ADMET predictions of Ac-Pef compounds showed favorable absorption and distribution, with no hepatotoxicity. A. crassiflora fruit peel showed hepatoprotective properties, indicating a promising natural source of bioactive molecules for prevention and therapy of diabetes complications.