Level of neurotransmitters in neuroamine-containing lung structures in different forms of tuberculosis

The aim of the study was to identify the features of variations in the localization of monoamines (catecholamines, serotonin)in the cell structures of autopsy material of lungs affected by tuberculosis. Material and methods. 165 cases of secondary pulmonary tuberculosis were studied. We studied 2500 histological preparations of patients aged 30 to 55 years, divided into 5 groups, corresponding to the forms of secondary tuberculosis (group 1-acute focal tuberculosis, group 2-fibro-focal tuberculosis, group 3-infiltrative tuberculosis, group 4-acute cavernous tuberculosis, group 5 - fibro-cavernous tuberculosis. To selectively detect neuroamine-containing structures of the lungs and adrenergic nerve fibers, the Falk-Hillarp luminescence-histochemical method was used in the modification of E. M. Krokhina, based on the reaction of neuroamine condensation with formaldehyde. Results. When using the Falk-Hillarp luminescence-histochemical method, mycobacteria of tuberculosis containing catecholamines and serotonin were detected in autopsy material of lungs affected by a specific inflammatory process, as well as neuroamine-containing granular luminescent cells and mast cells. Affected and unaffected areas of the lungs contain different amounts of the studied monoamines. The results of the study revealed the dependence of the number of cells and the content of the studied bioamines in them on the form of secondary tuberculosis. It was found that in small forms of secondary tuberculosis (acute focal, fibrotic-focal), the number of cells and quantitative parameters of the studied neurotransmitters (catecholamines, serotonin) in granular luminescent cells and mast cells change in the direction of increase. In destructive processes in the lungs (acute cavernous and fibrous-cavernous tuberculosis), the content of catecholamines in the studied structures in the affected area prevails over the control. The concentration of serotonin in the studied cells of the area of lung tissue affected by the tuberculosis process is reduced. The number of neuroamine-containing cells is significantly reduced. The maximum luminescence of catecholamines and serotonin in granular luminescent cells was determined in the infiltrative form of tuberculosis. In mast cells, the highest content of catecholamines was found in the group of acute cavernous tuberculosis, and serotonin in the group of the infiltrative form of the disease. In stained sections of the lungs in this form of tuberculosis, a luminescent pathway of lymphocytes was found. The nerve fibers detected at the sites of mycobacteria were also changed. They did not have a clear luminescence, looked "swollen", in places they did not have varicose veins. Conclusion. Comparing the results of the study with the literature data, it was found that pulmonary tuberculosis occurs as a delayed reaction, and Mycobacterium tuberculosis manifests itself as a corpuscular antigen.

Adrenergic Blockade by Nebivolol to Suppress Oral Squamous Cell Carcinoma Growth via Endoplasmic Reticulum Stress and Mitochondria Dysfunction

Adrenergic nerve fibers in the tumor microenvironment promote tumor growth and represent a potential target for cancer therapy. However, the effectiveness of targeting adrenergic nerve fibers for oral squamous cell carcinoma (OSCC) therapy needs to be evaluated by preclinical data. Herein, the 4NQO-induced and orthotopic xenograft OSCC mice models were established. We demonstrated that using 6OHDA chemical denervation as well as using nebivolol adrenergic blockade could halt the oral mucosa carcinogenesis. Our preclinical studies suggested that nebivolol, which is widely used to treat cardiovascular diseases, can be repositioned as a potential candidate to treat OSCC. Remarkably, we revealed the precise effect and mechanism of nebivolol on OSCC cells proliferation, cell cycle, and cell death. Administration of nebivolol could activate the endoplasmic reticulum (ER) stress signaling pathway through increasing the expression of inducible nitric oxide synthase, which subsequently triggers the integrated stress response and cell growth arrest. Simultaneously, ER stress also induced mitochondrial dysfunction in OSCC cells. We found that the accumulation of dysfunctional mitochondria with the impaired electron transport chain caused increasing reactive oxygen species production, which ultimately resulted in OSCC cell death. Altogether, our finding suggested a novel therapeutic opportunity for OSCC by targeting adrenergic nerve fibers, and repurposing nebivolol to treat OSCC can be represented as an effective strategy.

Dependence on Schwann Cell-Derived Laminin-γ1 Differentiates Early Lymphoid and Myeloid Development

Blood cell production is regulated by peripheral nerve fibers that innervate the bone marrow. However, little is known about the development or maintenance of hematopoietic innervation. Schwann cells (SCs) are the primary axon 'support cells' of the peripheral nervous system (PNS), and abnormal SC development is sufficient to impair peripheral nerve function. SCs are also the primary repair cell for the PNS which makes them an attractive therapeutic target for normalization of drug or malignancy-induced 'hematopoietic neuropathy'. We hypothesized that neural regulation of hematopoiesis is dependent on SC development. To test this hypothesis, we used the Myelin Protein Zero-Cre (MP0-Cre); Lamc1fl/fl mouse line in which laminin-γ1 expression is deleted from SC precursors and their progeny1. Early SC maturation is dependent on autocrine SC precursor-derived molecules such as laminin-γ1. SC differentiation arrests prior to axon sorting and ensheathment in MP0-Cre; Lamc1fl/fl mice, and causes a global peripheral neuropathy that persists throughout the lifetime of the animal. Preliminary hematopoietic analysis of 'steady state' MP0-Cre; Lamc1fl/fl and littermate control mice has shown the following: (1) MP0-Cre; Lamc1fl/fl bone marrow is innervated, and Cre-mediated gene recombination occurs in cells immunophenotypically consistent with SCs throughout the peripheral nervous system, including those in the bone marrow; (2) MP0-Cre; Lamc1fl/fl mice are lymphopenic but not neutropenic; (3) MP0-Cre; Lamc1fl/fl mice have significantly reduced spleen size and cellularity; and (4) MP0-Cre; Lamc1fl/fl bone marrow has an ~50% reduction in Lin-Sca-1+Kit+(LSK) cells (measured as a percentage of the Lin- compartment of the bone marrow). These results are consistent with earlier work by our groups in which we found that global Lamc1 gene deletion in adult mice induced peripheral blood lymphopenia, reduced spleen size, and a niche-dependent reduction of lymphoid progenitor and precursor cells that was secondary to increased lymphoid precursor cell apoptosis and reduced proliferation (UBC-CreERT2; Lamc1fl/fl mouse line). As with the SC-specific laminin-γ1 deficient mice, myelopoiesis was preserved in the UBC-CreERT2; Lamc1fl/fl mice. Based on results from MP0-Cre; Lamc1fl/fl and UBC-CreERT2; Lamc1fl/fl mice, we conclude that early lymphoid but not myeloid development requires laminin-γ1 expression by MP0-Cre-targetted niche cells, i.e. Schwann Cells. Our results are consistent with reports from other labs that hematopoietic sympathetic neuropathy promotes aberrant myeloid expansion at the expense of lymphopoiesis2. Going forward, we will determine whether lymphopoietic development is dependent on global versus laminin-specific SC-derived cues, and whether these signals are transmitted directly between SCs and lymphoid biased HSPCs or indirectly via other components of the hematopoietic niche. We anticipate that this line of investigation will provide molecular insights and pharmacologic targets for prevention and or normalization of the 'hematopoietic neuropathy' induced by diabetes, aging, neurotoxic chemotherapies and myeloid malignancies. REFERENCES: 1 Yu, W. M., Feltri, M. L., Wrabetz, L., Strickland, S. & Chen, Z. L. Schwann cell-specific ablation of laminin gamma1 causes apoptosis and prevents proliferation. J Neurosci25, 4463-4472, doi:10.1523/JNEUROSCI.5032-04.2005 (2005). 2 Maryanovich, M. et al. Adrenergic nerve degeneration in bone marrow drives aging of the hematopoietic stem cell niche. Nat Med24, 782-791, doi:10.1038/s41591-018-0030-x (2018). Disclosures No relevant conflicts of interest to declare.

Cutaneous adrenergic nerve blockade attenuates sweating during incremental exercise in habitually trained men

It remains unknown whether cutaneous adrenergic nerves functionally contribute to sweat production during exercise. This study examined whether cutaneous adrenergic nerve blockade attenuates sweating during incremental exercise, specifically in habitually trained individuals. Accordingly, 10 habitually trained and 10 untrained males (V̇o2max: 56.7 ± 5.4 and 38.9 ± 6.7 ml·kg−1·min−1, respectively; P < 0.001) performed incremental semirecumbent cycling (20 W/min) until exhaustion. Sweat rates (ventilated capsule) were measured at two bilateral forearm skin sites on which either 10 mM bretylium tosylate (BT) (an inhibitor of neurotransmitter release from sympathetic adrenergic nerve terminals) or saline (Control) was transdermally administered via iontophoresis. BT treatment delayed sweating onset in both groups (∼0.66 min; P = 0.001) and suppressed the sweat rate relative to the Control treatment at ≥70% relative total exercise time in trained individuals (each 10% increment; all P ≤ 0.009) but not in untrained counterparts ( P = 0.122, interaction between relative time × treatment). Changes in total sweat production at the BT site relative to the Control site were greater in trained individuals than in untrained counterparts (area under the curve, −0.86 ± 0.67 and −0.22 ± 0.39 mg/cm2, respectively; P = 0.023). In conclusion, we demonstrated that cutaneous adrenergic nerves do modulate sweating during incremental exercise, which appeared to be more apparent in habitually trained men (e.g., ≥70% maximum workload). Although our results indicated that habitual exercise training may augment neural adrenergic sweat production during incremental exercise, additional studies are required to confirm this possibility. NEW & NOTEWORTHY We demonstrated for the first time that cutaneous adrenergic nerves do modulate sweating during high-intensity exercise in humans (≥70% maximum workload). In addition, neural adrenergic sweating appeared to be greater in habitually trained individuals than in untrained counterparts, although further studies are necessary to confirm such a possibility. Nonetheless, the observations presented herein advance our understanding on human thermoregulation while providing new evidence for the neutral mediation of adrenergic sweating during exercise.