Ibtissem Ben Amara

Objective: This study investigated the effects of three chronic stress exposure models (permanent elimination, forced swimming, and food and water deprivation) on bone oxidative stress, structure, and metabolism in vivo. Methods: Adult rats were exposed to different stress conditions, while control animals were maintained under standard laboratory conditions. Bone morphological and histological parameters, oxidative stress biomarkers, antioxidant defense system, and mineral concentrations were assessed. Results: Stress exposure resulted in significant reductions in body weight, femur weight, and femur length compared to controls. A marked increase in oxidative stress biomarkers was observed in bone tissue, including lipid peroxidation, reactive oxygen species, hydroperoxides, hydrogen peroxide, protein carbonyls, and advanced oxidation protein products. In contrast, antioxidant defenses, including enzymatic activities and levels of glutathione, non-protein thiols, and vitamin C, was significantly decreased. Bone calcium and phosphorus levels were reduced, whereas their plasma concentrations were increased following stress exposure. Histological analysis confirmed the biochemical alterations, suggesting that chronic stress can disrupt bone integrity via oxidative mechanisms. Conclusions: These findings highlight the need for strategies to control and reduce stress-related disorders to maintain skeletal health under various chronic stress conditions.

Various therapeutic approaches have been explored to speed up wound healing, with angiogenesis being a crucial factor in this process and skin repair. This study shows that a polysaccharide extracted from the red alga Osmundea pinnatifida (PSOP) can promote angiogenesis and accelerate healing. The structural properties of PSOP were investigated using various techniques, including scanning electron microscopy, X-ray diffraction, Fourier–transform infrared spectroscopy, ultraviolet–-visible spectroscopy, and high-performance liquid chromatography coupled with a refractive index detector. Additionally, the in vitro antioxidant activity of PSOP was evaluated using the reducing power assay, total antioxidant capacity measurement, and DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging tests. The PSOP extract exhibited significant pro-angiogenic effects in the avian chorioallantoic membrane model. Furthermore, the efficacy of PSOP-based hydrogels for wound healing was assessed in vivo using an excision wound model in Wistar rats. The results indicated accelerated wound healing, increased collagen deposition, and enhanced tissue regeneration. Computational studies suggest that the observed wound healing and pro-angiogenic effects may be attributed to the affinity of the PSOP units for cyclooxygenase-2 and vascular endothelial growth factor. These findings support the potential use of PSOP as a bioactive agent in wound care.

Glyphosate (N-phosphonomethylglycine) is a widely used organophosphorus herbicide that inhibits the shikimate pathway, a crucial metabolic route responsible for the synthesis of aromatic amino acids in plants and certain microorganisms. Due to its broad-spectrum activity, glyphosate serves as the main active ingredient in various commercial herbicide formulations, including Roundup and Kalach 360 SL (KL). It poses a health hazard to animals and humans due to its persistence in soil, water erosion, and crops. The aim of our study was to continue the previous research to explore the impact of KL on bone using physico-chemical parameters and in silico studies after exposing female wistar rats for 60 days. The in silico study concerned the assessment of binding affinity and molecular interactions using computational modeling approach. The rats were allocated into three experimental groups: group 1 (n = 6) served as controls, while groups 2 and 3 received low and high doses (Dose 1: 126 mg/Kg and Dose 2: 315 mg/Kg) of KL dissolved in water, respectively. All rats were sacrificed after 60 days of exposure. XRD and FTIR spectrum analysis of bone tissues in female rats showed significant histoarchitectural changes associated with bone mineralization disruption. Our results have demonstrated that sub-chronic exposure of adult female rats to KL causes bone rarefaction, as confirmed by a previous histological study. This physico-chemical study has further confirmed the harmful impact of KL on the crystalline fraction of bone tissue, composed of hydroxyapatite crystals. In addition, the computational analyses showed that glyphosate binds to 3 Glu form of osteocalcin (3 Glu-OCN) (4MZZ) and decarboxylated osteocalcin (8I75) with good affinities and strong molecular interactions, which justified and supported the in vivo findings. In conclusion, KL may interfere with hydroxyapatite and osteocalcin and, therefore, impair bone remodeling and metabolism.

Background/Objectives: This study evaluated the potential of a polysaccharide (PCS) extracted from the brown alga Cystoseira spinosa as an antioxidant and anti-inflammatory agent. Collected off the coast of Alkhoms, Libya, PCS was investigated for its wound-healing and pro-angiogenic properties, addressing the need for natural bioactive compounds in therapeutic applications. Methods: The monosaccharide composition of PCS was analyzed using HPLC-RID, identifying glucuronic acid and xylose as major components. In vitro tests assessed antioxidant activity, while in vivo experiments on 24 rats evaluated wound healing. Rats were divided into four groups: control (saline), standard drug (CYTOL CENTELLA cream), glycerol, and glycerol+PCS. Wound healing was analyzed macroscopically, histologically, and biochemically. The chick chorioallantoic membrane (CAM) model assessed pro-angiogenic effects, and computational analyses explored COX-2 and VEGF pathways. Pharmacokinetic properties were also evaluated. Results: PCS demonstrated significant antioxidant activity and accelerated wound healing after 16 days, with improved wound appearance scores and increased collagen content. Histological analysis confirmed PCS outperformed the standard drug. The CAM model showed PCS increased blood vessel density, length, and junctions while reducing lacunarity. Computational analyses supported involvement of COX-2 and VEGF pathways. Pharmacokinetic assessments indicated good bioavailability, non-inhibition of CYP enzymes, and favorable skin permeability. Conclusions: PCS shows promise as a natural bioactive polymer for wound healing and tissue regeneration. Its antioxidant, anti-inflammatory, and pro-angiogenic properties, combined with favorable pharmacokinetics, highlight its therapeutic potential. This study provides new insights into the mechanisms of C. spinosa polysaccharides and their application in promoting tissue repair.

Various methods have been studied to speed up the wound healing process. Promoting the rapid development of blood vessels, also known as angiogenesis, is essential as this significantly accelerates skin regeneration. This study identified a polysaccharide from the red alga Osmundea pinnatifida (PSOP) that promotes angiogenesis and accelerates wound healing. Firstly, we analyzed the structural characteristics of PSOP using various techniques such as UV-visible spectrum, Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (X-RD), scanning electron microscopy (SEM), and high-performance liquid chromatography coupled to refractive index detector (HPLC-RID). We also evaluated the antioxidant properties of PSOP in vitro using tests for DPPH free radical scavenging capacity, iron reduction capacity (RPA), and total antioxidant capacity (TAC). Additionally, we observed a significant increase in new blood vessel formation in the chorioallantoic membrane model (CAM assay) using a fertilized hen egg, indicating the pro-angiogenic effect of PSOP. Furthermore, we tested the wound-healing potential of PSOP hydrogel in vivo using excision wounds in the Wistar rat model. The results showed a notable acceleration of wound closure and an improvement in tissue regeneration and collagen deposition quality within 11 days, indicating the strong wound-healing activity of PSOP. Our computational study suggested that the PSOP units bind to cyclooxygenase 2 (COX-2) and vascular endothelial growth factor (VEGF) with acceptable affinities and interactions, which might explain the observed beneficial wound healing properties and the pro-angiogenic effect seen in the experimental assays. Our findings support using the polysaccharide PSOP for wound treatment due to its antioxidant and pro-angiogenic potential.

1. In biological systems, trace elements such as zinc (Zn) and copper (Cu) are vital to human health (McEuen et al. 1992; Prasad 2003). These minerals are implicated in various metabolic processes,...

The purpose of this paper was to investigate the anti-inflammatory and anti-angiogenic activities of sulfated polysaccharide from C. tomentosum (PCT) using carrageenan (CARR)-induced paw edema in a rat model and anti-vasculogenic activity on a chorioallantoic membrane assay (CAM) model. Based on in vitro tests of anti-radical, total antioxidant, and reducing power activities, PCT presents a real interest via its antioxidant activity and ability to scavenge radical species. The in vivo pharmacological tests suggest that PCT possesses anti-inflammatory action by reducing paw edema and leukocyte migration, maintaining the redox equilibrium, and stabilizing the cellular level of several pro-/antioxidant system markers. It could significantly decrease the malondialdehyde levels and increase superoxide dismutase, glutathione peroxidase, and glutathione activities in local paw edema and erythrocytes during the acute inflammatory reaction of CARR. PCT pretreatment was effective against DNA alterations in the blood lymphocytes of inflamed rats and reduced the hematological alteration by restoring blood parameters to normal levels. The anti-angiogenic activity results revealed that CAM neovascularization, defined as the formation of new vessel numbers and branching patterns, was decreased by PCT in a dose-dependent manner, which supported the in silico bioavailability and pharmacokinetic findings. These results indicated the therapeutic effects of polysaccharides from C. tomentosum and their possible use as anti-proliferative molecules based on their antioxidant, anti-inflammatory, and anti-angiogenic activities.

Background: Acute poisonings (AP) are a significant public health problem, accounting for a high number of emergency department visits and thousands of deaths worldwide. This study aimed to assess the epidemiology of AP in an adult population admitted to Cayenne Hospital (French Guiana) and to investigate the clinical and sociodemographic characteristics. Methods: We conducted a monocentric retrospective study from January 2010 to December 2022, including patients over eighteen years of age who had been admitted to the emergency department of Cayenne Hospital for acute poisoning. Results: We included 425 patients. The median age was 34 years (IQR: 25–47). The sex ratio (M/F) was 0.52. A psychiatric disorder was found in 41.9% of patients. The Poisoning Severity Score (PSS) on admission was 1 or 2 for 84% of patients, and the mortality rate was 3.9%. The main involved toxicants were psychotropic drugs (43.1%), benzodiazepines (34.8%), and paracetamol (25.6%). The most lethal toxic was paraquat (5.2%). Intoxication was due to intentional self-poisoning in 84.2% of cases. Independent factors associated with severe poisoning (PSS 3 or 4) were chloroquine, neuroleptics, or paraquat poisoning; metabolic acidosis; and hyperglycemia (>5.5 mmol/L). The mortality rate was 3.9%, and the most involved toxic in death was paraquat. Conclusion: This study shows the frequent and deadly use of paraquat in APs in French Guiana. Urgent attention should be given to establishing a toxicovigilance monitoring framework and an antipoison center in the region.

In this study, we investigated for the first time the anti-inflammatory and immunomodulatory properties of crude polysaccharide (PSHT) extracted from green marine algae Halimeda tuna. PSHT exhibited anti-oxidant activity in vitro through scavenging 1, 1-diphenyl-2-picryl hydroxyl free radical, reducing Fe³⁺/ferricyanide complex, and inhibiting nitric oxide. PSHT maintained the erythrocyte membrane integrity and prevented hemolysis. Our results also showed that PSHT exerted a significant anti-edematic effect in vivo by decreasing advanced oxidation protein products and malondialdehyde levels and increasing the superoxide dismutase and glutathione peroxidase activities in rat’s paw model and erythrocytes. Interestingly, PSHT increased the viability of murine RAW264.7 macrophages and exerted an anti-inflammatory effect on lipopolysaccharide-stimulated cells by decreasing pro-inflammatory molecule levels, including nitric oxide, granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor-alpha (TNF-α). Our findings indicate that PSHT could be used as a potential immunomodulatory, anti-inflammatory, anti-hemolytic, and anti-oxidant agent. These results could be explained by the computational findings showing that polysaccharide building blocks bound both cyclooxygenase-2 (COX-2) and TNF-α with acceptable affinities.

The present study aimed to evaluate the in vitro antibacterial and antioxidant activities and the in vivo wound healing performance of a polysaccharide isolated from Glycyrrhiza glabra named PSG. It was structurally characterized by Fourier transformed infrared (FT-IR) spectroscopy, which confirmed the presence of different polysaccharides functional bands. The antioxidant capacity of PSG was determined in vitro and evaluated in vivo through the examination of wound healing capacity. Thirty two rats were randomly divided into four groups: group I was treated with physiological serum (negative control); group II was treated with “CYTOL CENTELLA^®”; group III was treated with glycerol and group IV was treated with polysaccharide. The response to treatments was assessed by macroscopic, histologic, and biochemical parameters. Data revealed that our sample exhibited potential antioxidant activities and accelerated significantly the wound healing process, after ten days of treatment, proved by the higher wound appearance scores and a higher content of collagen confirmed by histological examination, when compared with control and “CYTOL CENTELLA^®”. Overall, these findings proved that this polysaccharide isolated from Glycyrrhiza glabra could be considered as a natural bioactive polymer for therapeutic process in wound healing applications.