Anxiety leads to up-regulation of CD36 on the monocytes of chronic hepatitis B-infected patients

CD36 deficiency reduces chronic BBB dysfunction and scar formation and improves activity, hedonic and memory deficits in ischemic stroke

Ameliorating blood-brain barrier disruption and altering scar formation dynamics are potential strategies that may improve post-stroke recovery. CD36 is a class B scavenger receptor that plays a role in innate immunity, inflammation and vascular dysfunction and regulates post-stroke injury, neovascularization, reactive astrogliosis and scar formation. By subjecting WT and CD36KO mice to different MCAo occlusion durations to generate comparable acute lesion sizes, we addressed the role of CD36 in BBB dysfunction, scar formation and recovery. The majority of stroke recovery studies primarily focus on motor function. Here, we employed an extensive behavioral test arsenal to evaluate psychological and cognitive endpoints. While not evident during the acute phase, CD36 deficient mice displayed significantly attenuated BBB leakage and scar formation at three months after stroke compared to wild-type littermates. Assessment of motor (open field, rotarod), anxiety (plus maze, light-dark box), depression (forced swim, sucrose preference) and memory tests (water maze) revealed that CD36 deficiency ameliorated stroke-induced behavioral impairments in activity, hedonic responses and spatial learning and strategy switching. Our findings indicate that CD36 contributes to stroke-induced BBB dysfunction and scar formation in an injury-independent manner, as well as to the chronic motor and neurophysiological deficits in chronic stroke.

Depression Is Associated with Downregulation of IPS-1 in Chronic HBV-Infected Patients in a Sex-Dependent Manner

BACKGROUND

Depression and anxiety can modulate immune-related molecule expressions. The chronic HBV-infected (CHB) patients suffer from inappropriate immune responses. Additionally, psychological disorders are prevalent among the patients. Thus, depression and anxiety may alter immune-related molecule expression. This study aimed to examine IPS-1 and RIP1 mRNA levels in CHB patients suffering from various degrees of anxiety and depression.

METHODS

Sixty patients with CHB participated in this research and completed standard questionnaires to evaluate depression and anxiety. The expression levels of IPS-1 and RIP1 were examined using real-time PCR techniques.

RESULTS

The result revealed that although the expression of IPS-1 and RIP1 did not change in the CHB patients with various ranges of depression and anxiety, IPS-1 was significantly decreased in the male CHB patients who suffered from mild, moderate, and severe depression when compared to the patients with no depression.

CONCLUSION

So, it was hypothesized that depression may be associated with alteration in the expression of IPS-1 in a sex-dependent manner. In other words, it appears that the male CHB patients are at risk of depression-related alteration in immune-related gene expression.

A systematic review of the impact of psychosocial factors on immunity: Implications for enhancing BCG response against tuberculosis

BACKGROUND

Tuberculosis (TB) remains an urgent global public health priority, causing 1.5 million deaths worldwide in 2018. There is evidence that psychosocial factors modulate immune function; however, how this may influence TB risk or BCG vaccine response, and whether this pathway can be modified through social protection, has not been investigated. This paper aims to: a) systematically review evidence of how psychosocial factors influence the expression of biomarkers of immunity, and b) apply this general evidence to propose plausible TB-specific pathways for future study.

METHODS

Papers reporting on the impact of psychosocial stressors on immune biomarkers in relation to infectious disease risk were identified through a search of the databases MEDLINE, PsycINFO, Global Health and PsycEXTRA alongside reference list and citation searching of key papers. Data extraction and critical appraisal were carried out using a standardised form. The findings were tabulated and synthesised narratively by infectious disease category, and used to propose plausible mechanisms for how psychosocial exposures might influence immune outcomes relevant to TB and BCG response.

RESULTS

27,026 citations were identified, of which 51 met the inclusion criteria. The literature provides evidence of a relationship between psychosocial factors and immune biomarkers. While the direction and strength of associations is heterogenous, some overarching patterns emerged: adverse psychosocial factors (e.g. stress) were generally associated with compromised vaccine response and higher antibody titres to herpesviruses, and vice versa for positive psychosocial factors (e.g. social support).

CONCLUSIONS

The evidence identifies pathways linking psychosocial factors and immune response: co-viral infection and immune suppression, both of which are potentially relevant to TB and BCG response. However, the heterogeneity in the strength and nature of the impact of psychosocial factors on immune function, and lack of research on the implications of this relationship for TB, underscore the need for TB-specific research.