Hyperactive lateral habenula mediates the comorbidity between rheumatoid arthritis and depression-like behaviors

Glutamate-mediated antidepressant effects of Jieyu I formula via modulation of PFCCaMKII-LHbCaMKII/GABA circuitry in lipopolysaccharide-induced depression model

ETHNOPHARMACOLOGICAL RELEVANCE

Jieyu I Formula (JY-I) is an improved version of the classic formula "Sini San" documented in the books Shanghan Lun, which is known for regulating the liver and treating depression. However, the disturbance of neuronal signal transmission in the neural circuit of the brain is closely related to the occurrence of depression, yet its neural mechanism is still unclear.

AIM OF THE STUDY

This study aimed to observe the antidepressant effect of JY-I on depressed mice induced by lipopolysaccharide and its underlying central nervous system mechanisms, focusing on the prefrontal cortex (PFC) to lateral habenular nucleus (LHb) neural circuit in the depressed mice model.

MATERIALS AND METHODS

JY-I comprised herbs include Bupleurum chinense, Fructus Aurantii, Paeonia lactiflora, Lotus Seed Heart, Schisandra chinensis, and Hypericum perforatum, which are prepared in a ratio of 2:2:2:2:1:1. The mouse model of depression was induced by lipopolysaccharide. The antidepressant efficacy of JY-I was observed by behavioral tests. Observation of the PFC/LHb neuron activity in mice using in-vivo electrophysiological combined with optogenetic technology. Subsequently, the activity of the LHb neuron was observed using immunofluorescence staining analysis and Western blot. Inject Rabies virus into the LHb brain region and observe the projection of the PFC from upstream brain regions received by the LHb. Using chemogenetic techniques to activate/inhibit the PFC-LHb neural circuit and investigate the effect of JY-I on depression-like behaviors.

RESULTS

Depression-like behaviors in mice can be induced by intraperitoneal administration of lipopolysaccharide, the behavior changes were reversed with the administration of the JY-I. The combination of optogenetics and electrophysiological recording result indicates that JY-I activates glutamate (Glu) neurons in the PFC, thus maintaining an optimal excitatory/inhibitory (E/I) balance and ameliorating depression-like behaviors. Notably, the PFC, a crucial brain area for emotion regulation, exerts its antidepressant effect on downstream LHb region through the activation of Glu neurons.

CONCLUSIONS

JY-I can significantly improve lipopolysaccharide-induced depression-like behaviors. JY-I exerts antidepressant effects by activating the PFC Glu neurons projecting to the LHb, revealing a promising therapeutic target for depression.

Musculoskeletal Multimorbidity Burden and Trajectory in Relation to Later-Life Holistic Well-Being Among Middle-Aged and Elderly Individuals: A Prospective Study

OBJECTIVES

Understanding the patterns and implications of coexisting musculoskeletal conditions is crucial for developing effective management strategies and improving care for older adults. This study aimed to examine the associations between musculoskeletal multimorbidity burden and trajectory and holistic well-being among middle-aged and older adults.

METHODS

This prospective study employed data from nine consecutive waves of the English Longitudinal Study of Aging (ELSA), spanning 2002-2018. We used latent class trajectory models (LCTM) to identify groups based on changes in musculoskeletal multimorbidity status. Subsequently, we employed linear mixed models to investigate the associations between musculoskeletal disease burden, trajectory groups, and seven dimensions of holistic well-being: Activities of Daily Living (ADLs), Instrumental Activities of Daily Living (IADLs), depression, memory, loneliness, social interactions, and life satisfaction.

RESULTS

In total, 5272 participants (mean age: 71.9 years; SD: 8.9) were included in the final analysis. Four distinct trajectories were identified: a low-burden group (48.37%), an emerging group (14.76%), a moderate-burden group (26.00%), and a persistent burden group (10.87%). After adjustment, the findings demonstrate that the musculoskeletal disorder burden significantly impacts ADLs, depression, memory, social interactions, and life satisfaction in middle-aged and older adults, with minor effects on IADLs and loneliness. Moreover, with the escalation of the burden, its impact significantly intensifies (p for trend is < 0.001). Compared with the low-burden group, participants in both the moderate and persistent burden groups exhibited significantly lower capabilities in ADLs, poorer memory, increased social interactions, and lower life satisfaction. The emerging group displayed a similar trend, though without statistically significant results.

CONCLUSIONS

Our study suggests that the extent and persistence of musculoskeletal disease burden can significantly affect holistic well-being among middle-aged and older individuals.

A History of Psycho-Neuro-Endocrine Immune Interactions in Rheumatic Diseases

BACKGROUND

All active scientists stand on the shoulders of giants and many other more anonymous scientists, and this is not different in our field of psycho-neuro-endocrine immunology in rheumatic diseases. Too often, the modern world of publishing forgets about the collective enterprise of scientists. Some journals advise the authors to present only literature from the last decade, and it has become a natural attitude of many scientists to present only the latest publications. In order to work against this general unempirical behavior, neuroimmunomodulation devotes the 30th anniversary issue to the history of medical science in psycho-neuro-endocrine immunology.

SUMMARY

Keywords were derived from the psycho-neuro-endocrine immunology research field very well known to the authors (R.H.S. has collected a list of keywords since 1994). We screened PubMed, the Cochran Library of Medicine, Embase, Scopus database, and the ORCID database to find relevant historical literature. The Snowballing procedure helped find related work. According to the historical appearance of discoveries in the field, the order of presentation follows the subsequent scheme: (1) the sensory nervous system, (2) the sympathetic nervous system, (3) the vagus nerve, (4) steroid hormones (glucocorticoids, androgens, progesterone, estrogens, and the vitamin D hormone), (5) afferent pathways involved in fatigue, anxiety, insomnia, and depression (includes pathophysiology), and (6) evolutionary medicine and energy regulation - an umbrella theory.

KEY MESSAGES

A brief history on psycho-neuro-endocrine immunology cannot address all relevant aspects of the field. The authors are aware of this shortcoming. The reader must see this review as a viewpoint through the biased eyes of the authors. Nevertheless, the text gives an overview of the history in psycho-neuro-endocrine immunology of rheumatic diseases.

Regional Changes in Brain Biomolecular Markers in a Collagen-Induced Arthritis Rat Model

BACKGROUND

The effects of collagen-induced arthritis (CIA), a model of systemic inflammation, on brain regional molecular markers associated with neurological disorders are uncertain.

OBJECTIVE

This study investigated the brain regional molecular changes in markers associated with inflammation and neuronal dysfunction in a CIA model.

METHODS

Fourteen male Sprague Dawley rats were divided into control (n = 5) or CIA (n = 9) groups. 10 weeks after CIA induction, brain tissue was collected. Brain regional mRNA expression of inflammatory markers (IL-1β and IL-6), apoptotic markers (BAX and Bcl2) and neurotrophic factors (BDNF, CREB and TrkB) was determined. Monoamine distribution and abundance in different brain regions were determine by mass spectrometry imaging (MSI).

RESULTS

Neuroinflammation was confirmed in the CIA group by increased IL-β mRNA expression, concurrent with an increased BAX/Bcl2 ratio. The mRNA expression of CREB was increased in the midbrain and hippocampus while BDNF was increased and TrkB was decreased across all brain regions in CIA compared to control animals. Serotonin was decreased in the midbrain and hippocampus while dopamine was decreased in the striatum of CIA rats, compared to controls.

CONCLUSION

CIA resulted in neuroinflammation concurrent with an apoptotic state and aberrant expression of neurotrophic factors and monoamines in the brain, suggestive of neurodegeneration.