Pathophysiology linking depression and type 2 diabetes: Psychotherapy, physical exercise, and fecal microbiome transplantation as damage control

Abstract

Diabetes increases the likelihood of developing depression and vice versa. Research on this bidirectional association has somewhat managed to delineate the interplay among implicated physiological processes. Still, further exploration is required in this context. This review addresses the comorbidity by investigating suspected common pathophysiological mechanisms. One such factor is psychological stress which disturbs the hypothalamic–pituitary–adrenal axis causing hormonal imbalance. This includes elevated cortisol levels, a common biomarker of both depression and diabetes. Disrupted insulin signaling drives the hampered neurotransmission of serotonin, dopamine, and norepinephrine. Also, adipokine hormones such as adiponectin, leptin, and resistin and the orexigenic hormone, ghrelin, are involved in both depression and T2DM. This disarray further interferes with physiological processes encompassing sleep, the gut–brain axis, metabolism, and mood stability. Behavioral coping mechanisms, such as unhealthy eating, mediate disturbed glucose homeostasis, and neuroinflammation. This is intricately linked to oxidative stress, redox imbalance, and mitochondrial dysfunction. However, interventions such as psychotherapy, physical exercise, fecal microbiota transplantation, and insulin‐sensitizing agents can help to manage the distressing condition. The possibility of glucagon‐like peptide 1 possessing a therapeutic role has also been discussed. Nonetheless, there stands an urgent need for unraveling new correlating targets and biological markers for efficient treatment.

A network perspective on the ecology of gut microbiota and progression of Type 2 Diabetes: linkages to keystone taxa in a Mexican cohort

“…According to our multidimensional analysis, Alistipes can be a potential biomarker of the development of T2D. Still, further studies will be necessary in the near future to better de ne the role of this genus when T2D is accompanied by other comorbidities [73]. For instance, it has been reported that T2D patients have higher levels of depression incidence [74].…”

Neuropeptides as the Shared Genetic Crosstalks Linking Periodontitis and Major Depression Disorder

“…Thereby, a link between obesity and MDD was reported [ 36 ]. Moreover, RETN is involved in the interrelationship between MDD and diabetes, whereby neuroinflammation was reported to be of certain relevance [ 37 ]. This is a potential and interesting connecting point of MDD and PD; RETN was found to be elevated in gingival crevicular fluid and serum of patients with PD, although this was not related to systemic inflammatory diseases [ 38 ].…”

Prevalence and Clinical Significance of Occult Pulmonary Infection in Elderly Patients with Type 2 Diabetes Mellitus

“…For patients with senile dementia, the brainstem had poor regulation of respiratory function, and the lungs had a greatly diminished ability to clear pathogens, which, combined with the fact that they often present with language impairment and had difficulty expressing subjective sensation, thereby delaying the treatment [ 34 ]. Studies have shown that multiple neuroendocrine hormone abnormalities are present in patients with diabetes mellitus, manifested by glucocorticoid hypersecretion and dysfunction of hypothalamo-hypophyseal-thyroidal axis (HHTA) [ 35 – 37 ]. Moreover, with increasing age, HHTA also becomes progressively aged, leading to hypothyroidism manifested by reduced respiration, hypothermia, and hyporeflexia, which can mask infectious symptoms and lead to occult pulmonary infections [ 38 – 40 ].…”