Antibiotics with therapeutic effects on spinal cord injury: a review

Dual-directional regulation of spinal cord injury and the gut microbiota

There is increasing evidence that the gut microbiota affects the incidence and progression of central nervous system diseases via the brain-gut axis. The spinal cord is a vital important part of the central nervous system; however, the underlying association between spinal cord injury and gut interactions remains unknown. Recent studies suggest that patients with spinal cord injury frequently experience intestinal dysfunction and gut dysbiosis. Alterations in the gut microbiota can cause disruption in the intestinal barrier and trigger neurogenic inflammatory responses which may impede recovery after spinal cord injury. This review summarizes existing clinical and basic research on the relationship between the gut microbiota and spinal cord injury. Our research identified three key points. First, the gut microbiota in patients with spinal cord injury presents a key characteristic and gut dysbiosis may profoundly influence multiple organs and systems in patients with spinal cord injury. Second, following spinal cord injury, weakened intestinal peristalsis, prolonged intestinal transport time, and immune dysfunction of the intestine caused by abnormal autonomic nerve function, as well as frequent antibiotic treatment, may induce gut dysbiosis. Third, the gut microbiota and associated metabolites may act on central neurons and affect recovery after spinal cord injury; cytokines and the Toll-like receptor ligand pathways have been identified as crucial mechanisms in the communication between the gut microbiota and central nervous system. Fecal microbiota transplantation, probiotics, dietary interventions, and other therapies have been shown to serve a neuroprotective role in spinal cord injury by modulating the gut microbiota. Therapies targeting the gut microbiota or associated metabolites are a promising approach to promote functional recovery and improve the complications of spinal cord injury.

Traumatic Human Spinal Cord Injury: Are Single Treatments Enough to Solve the Problem?

Traumatic spinal cord injury (SCI) results in partial or complete motor deficits, such as paraplegia, tetraplegia, and sphincter control, as well as sensory disturbances and autonomic dysregulation such as arterial hypotension, lack of sweating, and alterations in skin lability. All this has a strong psychological impact on the affected person and his/her family, as well as costs to healthcare institutions with an economic burden in the short, medium, and long terms. Despite at least forty years of experimental animal studies and several clinical trials with different therapeutic strategies, effective therapy is not universally accepted. Most of the published works on acute and chronic injury use a single treatment, such as medication, trophic factor, transplant of a cell type, and so on, to block some secondary injury mechanisms or promote some mechanisms of structural/functional restoration. However, despite significant results in experimental models, the outcome is a moderate improvement in muscle strength, sensation, or eventually in sphincter control, which has been considered non-significant in human clinical trials. Here we present a brief compilation of successful individual treatments that have been applied to secondary mechanisms of action. These studies show limited neuroprotective or neurorestorative approaches in animal models and clinical trials. Thus, the few benefits achieved so far represent a rationale to further explore other strategies that seek better structural and functional restoration of the injured spinal cord.

Dapsone improves the vincristine-induced neuropathic nociception by modulating neuroinflammation and oxidative stress

BACKGROUND

Peripheral neuropathy is a dose-limiting adverse effect of vincristine (VCR) in cancer chemotherapies. Dapsone is commonly used for the prevention of opportunistic infections following cancer therapies. Therefore, a high rate of VCR and dapsone co-administration has occurred in leukemias. Recently neuroprotective effects of dapsone have been reported in various diseases.

OBJECTIVES

Regarding the physiopathology of VCR-induced peripheral neuropathy (VIPN) and dapsone neuroprotection, this study evaluated the effect of dapsone on VIPN.

METHODS

VIPN was induced by VCR injection (0.5 mg/kg IP, every other day, 1 week) in male Wistar rats. In the treatment group, dapsone(12.5 mg/kg IP, 1 week) was injected 30 min before VCR. Hot plate, Von Frey, motor neuron conduction velocity (MNCV), and histopathological tests were applied. The levels of TNF-α and NF-kB in the sciatic nerve and caspase-3 activity in dorsal root ganglion were measured by the ELISA method. The levels of malondialdehyde (MDA) and Glutathione (GSH) in the sciatic nerve were measured by spectrophotometry and colorimetric assays.

RESULTS

VIPN was observed as araised thermal and mechanical threshold, reduced MNCV, and sciatic nerve demyelination. However, dapsone reduced the mechanical and thermal threshold and improved the MNCV. Also, dapsone reduced TNF-α, NF-kB, MDA, and Caspase-3 activity, and increased the GSH level in the sciatic nerve. Moreover, dapsone prevented VCR-induced demyelination in the sciatic nerve.

CONCLUSION

This research demonstrated that dapsone could be used as a protective drug against VIPN. It improves the impaired thermal and mechanical sensations by reducing inflammatory, oxidant, and apoptosis factors and preventing demyelination in the sciatic nerve.

Dapsone, More than an Effective Neuro and Cytoprotective Drug

BACKGROUND

Dapsone (4,4'-diamino-diphenyl sulfone) is a synthetic derivative of sulfones, with the antimicrobial activity described since 1937. It is also a drug traditionally used in dermatological therapies due to its anti-inflammatory effect. In recent years its antioxidant, antiexcitotoxic, and antiapoptotic effects have been described in different ischemic damage models, traumatic damage, and models of neurodegenerative diseases, such as Parkinson's (PD) and Alzheimer's diseases (AD). Finally, dapsone has proven to be a safe and effective drug as a protector against heart, renal and pulmonary cells damage; that is why it is now employed in clinical trials with patients as a neuroprotective therapy by regulating the main mechanisms of damage that lead to cell death ObjectiveThe objective of this study is to provide a descriptive review of the evidence demonstrating the safety and therapeutic benefit of dapsone treatment, evaluated in animal studies and various human clinical trials Methods: We conducted a review of PubMed databases looking for scientific research in animals and humans, oriented to demonstrate the effect of dapsone on regulating and reducing the main mechanisms of damage that lead to cell death ConclusionThe evidence presented in this review shows that dapsone is a safe and effective neuro and cytoprotective treatment that should be considered for translational therapy.