Association of Alzheimer's dementia with oral bacteria, vitamin B12, folate, homocysteine levels, and insulin resistance along with its pathophysiology, genetics, imaging, and biomarkers

Vitamin intake and periodontal disease: a meta-analysis of observational studies

OBJECTIVE

A meta-analysis was performed to assess the epidemiological correlation between dietary intake of various types of vitamin intake and the risk of periodontal disease.

METHODS

A comprehensive computerized search was conducted in eight databases, namely PubMed, Web of Science, Embase, Cochrane Library, China Biology Medicine Disc, CNKI, VIP, and WanFang Database, and a random effect model was applied to combine pooled odds ratio (ORs) with corresponding 95% confidence intervals (CIs) of the included studies, and the sensitivity analysis was performed to explore the impact of a single study on the comprehensive results.

RESULTS

We finally included 45 effect groups from 23 observational studies, with a total number of study participants of 74,488. The results showed that higher levels of vitamin A (OR: 0.788, 95% CI: 0.640-0.971), vitamin B complex (OR: 0.884, 95% CI: 0.824-0.948), vitamin C (OR: 0.875, 95% CI: 0.775-0.988), vitamin D (OR: 0.964, 95% CI: 0.948-0.981), and vitamin E (OR: 0.868, 95% CI: 0.776-0.971) intake all were negatively correlated with periodontal disease. After removing each study, leave-one-out sensitivity analysis indicated no significant change in the overall results of any of the five meta-analyses.

CONCLUSIONS

The results from this meta-analysis demonstrated a negative association between high-dose vitamin A, vitamin B complex, vitamin C, vitamin D, and vitamin E consumption and the likelihood of developing periodontal disease, revealing the significant role of vitamins in preventing periodontal disease.

The Multifaceted S100B Protein: A Role in Obesity and Diabetes?

The S100B protein is abundant in the nervous system, mainly in astrocytes, and is also present in other districts. Among these, the adipose tissue is a site of concentration for the protein. In the light of consistent research showing some associations between S100B and adipose tissue in the context of obesity, metabolic disorders, and diabetes, this review tunes the possible role of S100B in the pathogenic processes of these disorders, which are known to involve the adipose tissue. The reported data suggest a role for adipose S100B in obesity/diabetes processes, thus putatively re-proposing the role played by astrocytic S100B in neuroinflammatory/neurodegenerative processes.

Vitamin B12 Deficiency and the Nervous System: Beyond Metabolic Decompensation-Comparing Biological Models and Gaining New Insights into Molecular and Cellular Mechanisms

Vitamin B12 (VitB12) is a micronutrient and acts as a cofactor for fundamental biochemical reactions: the synthesis of succinyl-CoA from methylmalonyl-CoA and biotin, and the synthesis of methionine from folic acid and homocysteine. VitB12 deficiency can determine a wide range of diseases, including nervous system impairments. Although clinical evidence shows a direct role of VitB12 in neuronal homeostasis, the molecular mechanisms are yet to be characterized in depth. Earlier investigations focused on exploring the biochemical shifts resulting from a deficiency in the function of VitB12 as a coenzyme, while more recent studies propose a broader mechanism, encompassing changes at the molecular/cellular levels. Here, we explore existing study models employed to investigate the role of VitB12 in the nervous system, including the challenges inherent in replicating deficiency/supplementation in experimental settings. Moreover, we discuss the potential biochemical alterations and ensuing mechanisms that might be modified at the molecular/cellular level (such as epigenetic modifications or changes in lysosomal activity). We also address the role of VitB12 deficiency in initiating processes that contribute to nervous system deterioration, including ROS accumulation, inflammation, and demyelination. Consequently, a complex biological landscape emerges, requiring further investigative efforts to grasp the intricacies involved and identify potential therapeutic targets.

Advances in the Study of the Pathology and Treatment of Alzheimer's Disease and Its Association with Periodontitis

Alzheimer's disease (AD) has become one of the leading causes of health problems in the elderly, and studying its causes and treatments remains a serious challenge for researchers worldwide. The two main pathological features of Alzheimer's disease are the extracellular deposition of β-amyloid (Aβ) to form senile plaques and the intracellular aggregation of hyperphosphorylated Tau protein to form neurofibrillary tangles (NFTs). Researchers have proposed several hypotheses to elucidate the pathogenesis of AD, but due to the complexity of the pathophysiologic factors involved in the development of AD, no effective drugs have been found to stop the progression of the disease. Currently, the mainstay drugs used to treat AD can only alleviate the patient's symptoms and do not have a therapeutic effect. As researchers explore interactions among diseases, much evidence suggests that there is a close link between periodontitis and AD, and that periodontal pathogenic bacteria can exacerbate Aβ deposition and Tau protein hyperphosphorylation through neuroinflammatory mechanisms, thereby advancing the pathogenesis of AD. This article reviews recent advances in the pathogenesis of AD, available therapeutic agents, the relevance of periodontitis to AD, and mechanisms of action.

Investigation of soybean lipophilic proteins as carriers for vitamin B12: Focus on interaction mechanism, physicochemical functionality, and digestion characteristics

This study aimed to explore the interaction mechanism between soybean lipophilic protein (LP) and vitamin B₁₂ and the potential of LP as a vitamin B₁₂ carrier. The results of spectroscopy indicated that the interaction between vitamin B₁₂ and LP changed the conformation of LP and exposed hydrophobic groups largely. The results of molecular docking revealed that vitamin B₁₂ interacted with LP through a hydrophobic pocket embedded on the surface of LP. With the enhancement of the interaction between LP and vitamin B₁₂, the particle size of the LP-vitamin B₁₂ complex gradually decreased to 588.31 nm and the absolute value of zeta potential gradually increased to 26.82 mV. Meanwhile, the LP-vitamin B₁₂ complex showed excellent physicochemical properties and digestive characteristics. The present work enriched the means of vitamin B₁₂ protection and provided a theoretical basis for applying the LP-vitamin B₁₂ complex in food systems.