Preventive Effect of Limosilactobacillus fermentum SCHY34 on Lead Acetate-Induced Neurological Damage in SD Rats.

Lead poisoning caused by lead pollution seriously affects people's health. Lactic acid bacteria has been shown to be useful for biological scavenging of lead. In this experiment, Sprague-Dawley (SD) rats were treated with 200 mg/L of lead acetate solution daily to induce chronic lead poisoning, and oral Limosilactobacillus fermentum (L. fermentum) SCHY34 to study its mitigation effects and mechanisms on rat neurotoxicity. The L. fermentum SCHY34 showed competent results on in vitro survival rate and the lead ion adsorption rate. Animal experiments showed that L. fermentum SCHY34 maintained the morphology of rat liver, kidney, and hippocampi, reduced the accumulation of lead in the blood, liver, kidney, and brain tissue. Further, L. fermentum SCHY34 alleviated the lead-induced decline in spatial memory and response capacity of SD rats, and also regulated the secretion of neurotransmitters and related enzyme activities in the brain tissue of rats, such as glutamate (Glu), monoamine oxidase (MAO), acetylcholinesterase (AchE), cyclic adenosine monophosphate (cAMP), and adenylate cyclase (AC). In addition, the expression of genes related to cognitive capacity, antioxidation, and anti-apoptotic in rat brain tissues were increased L. fermentum SCHY34 treatment, such as brain-derived neurotrophic factor (BDNF), c-fos, c-jun, superoxide dismutase (SOD)1/2, Nuclear factor erythroid 2-related factor 2 (Nrf2), and B-cell lymphoma 2 (Bcl-2), and so on. L. fermentum SCHY34 showed a great biological scavenging and potential effect on alleviating the toxicity of lead ions.

Lactobacillus fermentum CQPC08 protects rats from lead-induced oxidative damage by regulating the Keap1/Nrf2/ARE pathway.

In this experiment, Lactobacillus fermentum CQPC08 (LF-CQPC08) isolated from traditionally fermented pickles was used to study its mitigation effect on lead acetate-induced oxidative stress and lead ion adsorption capacity in rats. In vitro experiments showed that the survival rate in artificial gastric juice and the growth efficiency in artificial bile salt of LF-CQPC08 was 93.6% ± 2.2% and 77.2% ± 0.8%, and the surface hydrophobicity rate was 45.5% ± 0.3%. The scavenging rates of hydroxyl radical, superoxide anion, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) were 47.8% ± 0.9%, 63.9% ± 1.2%, and 83.6% ± 1.5%, respectively, and the reduction power was 107.3 ± 2.8 µmol L-1. LF-CQPC08 could not only adsorb 76.9% ± 1.0% lead ions in aqueous solution but also reduce the lead content in serum, liver, kidneys, and brain tissue of Sprague-Dawley (SD) rats, as well as maintain the cell structure and tissue state of the liver and kidneys. In addition, by examining the indicators of inflammation and oxidation in the serum, liver, and kidneys of SD rats, we found that LF-CQPC08 can reduce the proinflammatory factors interleukin (IL)-1 beta (1ß), IL-6, tumor necrosis factor alpha, and interferon gamma in the body, increase the level of anti-inflammatory factor IL-10, enhance the activity of antioxidant enzymes such as superoxide dismutase and catalase and glutathione levels in serum and organ tissues, and reduce the production of reactive oxygen species and accumulation of lipid peroxide malondialdehyde. LF-CQPC08 can also activate the Keap1/Nrf2/ARE signaling pathway to promote high-level expression of the downstream antioxidants heme oxygenase 1 (HO-1), NAD(P)H : quinone oxidoreductase 1 (NQO1), and γ-glutamylcysteine synthetase (γ-GCS). As food-grade lactic acid bacteria, LF-CQPC08 has great potential and research value in removing heavy metals from food and alleviating the toxicity of heavy metals in the future.

Effects of synthetic colloid and crystalloid solutions on hemorheology in vitro and in hemorrhagic shock.

BACKGROUND: Plasma expanders are commonly used in the management of critically ill patients, which may exhibit altered hemorheology. We evaluated the effects of various synthetic colloids and Lactated Ringer's (LR) solution on hemorheological parameters in vitro and in a rodent hemorrhagic shock model. METHODS: For the in vitro experiments, rat blood was incubated with hydroxyethyl starch (HES) 130/0.4, HES 200/0.5, succinylated gelatine (GEL), or LR at various ratios. The control consisted of blood without dilution. The hemorheological parameters were measured after a 15-min incubation. For the in vivo study, rats were subjected to a severe volume-controlled hemorrhage and were resuscitated using a colloid solution (HES 130/0.4, HES 200/0.5, or GEL) or LR. The hemorheological parameters were measured 2 h after resuscitation. RESULTS: The GEL significantly elevated the plasma viscosity compared to the other groups. In the in vitro study, GEL and LR accelerated the erythrocyte aggregation. There was no significant difference between HES 130/0.4, HES 200/0.5, and control groups regarding the aggregation amplitude and index. In the in vivo study, the aggregation amplitude increased significantly in the GEL group compared to the HES 130/0.4, HES 200/0.5, LR, and sham groups. There was no significant difference between the groups with respect to the elongation index in vivo. CONCLUSIONS: Hydroxyethyl starch did not change the erythrocyte aggregation compared to the control. GEL significantly accelerates the erythrocyte aggregation and elevates the plasma viscosity compared to hydroxyethyl starch. The in vitro hemorheological measurements most likely provide hints for the in vivo study.

Measurement of the methemoglobin concentration using Raman spectroscopy.

Methemoglobin concentration is an important pathophysiological biomarker, reflecting the oxygen-carrying and oxygen-releasing capabilities of hemoglobin (Hb). Raman spectroscopy is used to develop a novel technique for determining the methemoglobin concentration. Raman activity combined with two-dimensional correlation analysis is an attractive method for investigating Hb oxidation, exhibiting several relevant peaks in the range of 1200-1650 cm(-1). Methemoglobin concentration is estimated by measuring the intensity of Raman peaks in the ranges of 1210-1230 cm(-1) and 1340-1380 cm(-1) with 785-nm excitation. The correlation between Raman-based methemoglobin concentration estimations and the methemoglobin concentration measured using spectrophotometry was highly significant. These results suggest the potential of Raman spectroscopy as a new quantitative approach to determine the methemoglobin concentration.

Heating pad for the bleeding: external warming during hemorrhage improves survival.

BACKGROUND: Hypothermia is common during hemorrhagic shock. To warm the victims or not has been controversial. This study aims to investigate the effect of warming during the initial time of hemorrhage on body temperature, blood pressure, and survival in rat hemorrhagic shock models. METHODS: Forty anesthetized rats were divided into control group (n = 20) and warming group (n = 20). The rats of control group were placed on a wooden pad without heating, and the rats of warming group were placed on a heating pad maintained at 37°C ± 0.1°C. Blood withdrawal reached 40% of the total blood volume within 60 minutes. Numbers of survival rats, rectal temperature, and mean arterial pressure (MAP) were recorded when blood loss reached 0 (T0), 20% (T20), 30% (T30), and 40% (T40) of the total blood volume, respectively. RESULTS: Rectal temperature and MAP decrease gradually in both groups during hemorrhage. Warming continuously makes the rectal temperature of the warming group (36.68°C ± 0.63°C) slightly higher than that of the control group (36.17°C ± 0.69°C) at T0. The rectal temperature and MAP of the warming group are higher than that of the control group at T20, T30, and T40 (p < 0.05). Survival rates of the warming group are higher than that of the control group (p < 0.01). CONCLUSIONS: Warming during hemorrhage may prevent exacerbation of hypothermia and hypotension and therefore improve survival.

Nitric oxide inhalation, a proposed strategy for early treatment of hemorrhagic shock.

Nitric oxide (NO), an endothelial-derived relaxing factor, plays important roles in a variety of pathophysiological conditions such as hemorrhagic shock (HS). So far, the impact of NO administration in HS treatment has been controversial. Through literature review, we summarize here the biphasic effects of NO in early and late phases of HS. Evidence suggests that NO administration is beneficial in the early stage while detrimental in the late stage of HS. We further propose inhalation of NO as a novel therapeutic strategy for the treatment of HS in the early stage.

Sodium alginate as viscosity modifier may induce aggregation of red blood cells.

Viscosity of blood substitutes is among the important determinants to restore microcirculation. Sodium alginate (SA) is always mentioned as "viscosity modifier" in creating blood substitutes. In the present study, the whole blood was diluted using SA solutions to final hematocrits of 10%, 20%, and 35%, respectively. The whole blood viscosity (WBV) at different shear rates, plasma viscosity (PV), and rheological behavior of red blood cells (RBCs) was studied in vitro. The results show that SA may induce RBCs aggregation in a dose-dependent manner. Furthermore, the effect of SA on RBCs aggregation maybe involve the regulation of microcirculation.