: Alzheimer's disease (AD) is a neurodegenerative condition characterized by progressive cognitive deterioration, including deficits in memory and other cognitive functions. Oxidative stress and free radical damage play significant roles in its pathogenesis. This study aimed to investigate the potential anti-inflammatory and neuroprotective effects of Pistacia atlantica gum (administered at doses of 50 and 100 mg/kg for 14 days) in a rat model of AD induced by aluminum chloride (AlCl3). Behavioral changes were assessed using open field, passive avoidance, and elevated plus maze tests. Additionally, nitrite levels, nuclear factor-kappa B (NF-κB), brain-derived neurotrophic factor (BDNF), and immunostaining were evaluated. Administration of P. atlantica gum significantly increased step-through latency in the passive avoidance test (P < 0.01 and P < 0.001), enhanced mobility in the open field test (P < 0.01 and P < 0.001), and reduced anxiety-like behaviors in the elevated plus maze (P < 0.001) compared to the AlCl3 group. Treatment with the gum partially normalized the elevated levels of NF-κB and the decreased levels of BDNF caused by AlCl3 exposure. Our findings suggest that P. atlantica gum administration may alleviate oxidative stress, neuroinflammation, and cognitive impairment in AD rats.

The human microbiome refers to the genomic content of microorganisms inhabiting the human body, including the lungs, oral cavity, intestinal tract, esophagus, and other areas. The human oral microbiota is a diverse and complex ecosystem that includes bacteria, microeukaryotes, archaea, and viruses. These communities have a highly structured biogeography resulting from the various microenvironments in the oral cavity, shaping local metabolic exchange. Dietary nitrate (NO₃^-) is an ion naturally present in vegetables, especially leafy greens. When consumed, it leads to the production of nitric oxide (NO). This bioactive molecule benefits bodily functions like host defense and neuronal communication and improves vascular and metabolic health. Dietary NO₃^- is reduced to NO via the nitrate-nitrite-NO pathway, facilitated by nitrate-reducing bacteria inside the oral cavity. NO has a leading role in different types of diseases, including cancer, cardiovascular disease, and diabetes. The bioavailability of NO is greatly enhanced by the activity of bacteria residing in the mouth, which reduces NO₃^-to NO₂^- and increases the concentration of circulating NO₂^-. NO is the key to causing different malignancies, including gastrointestinal cancers. NO can cause cell death by inducing DNA damage and anti-apoptotic signaling pathways. Low to moderate levels of NO derived from tumors can activate angiogenesis and promote an invasive phenotype, while high levels of NO may have an anti-tumor effect in protecting against cancer. In this review, we intend to discuss the human microbiome, dietary NO₃^-consumption, the vital role of NO in the human body, types of cancers, and treatments based on it.

Pancreatic islet encapsulation has long been considered as a groundbreaking solution capable of reducing dependence on lengthy immune suppression protocols while boosting the receptivity of transplanted cells.

The urethra reconstruction using tissue engineering is a promising approach in clinical and preclinical studies in recent years. Generally, regenerative medicine comprises cells, bioactive agents, and biomaterial scaffolds to reconstruct tissue. For the restoration of extended urethral injury are incorporated autologous grafts or flaps from the skin of the genital area and buccal mucosa are utilized. However, biomaterial grafts with cells or growth factors are investigated to enhance these grafts natural and synthetic biomaterials were investigated for pre-clinical studies in the form of decellularization tissues, nanofiber/ microfiber, film, and foam grafts that determined safety and efficiency. In this regard, skin grafts, bladder epithelium, buccal mucosa, small intestinal submucosa, tissue-engineered buccal mucosa, and polymeric nanofibers in clinical trials were examined, and promising and diverse outcomes were acquired. Even though, one of the challenges of the reconstruction of the urethra is resistance to urine pressure and its ability to be sutured, which could be solved by the proper adjustment of the physicochemical characteristics of the graft. Urethra engineering faces challenges due to necrosis caused by a lack of angiogenesis and fibrosis, which require further investigation in future studies.