Polycationic phosphorous dendrimer potentiates multiple antibiotics against drug-resistant mycobacterial pathogens

Mycobacterium tuberculosis (Mtb), causative agent of tuberculosis (TB) and non-tubercular mycobacterial (NTM) pathogens such as Mycobacterium abscessus are one of the most critical concerns worldwide due to increased drug-resistance resulting in increased morbidity and mortality. Therefore, focusing on developing novel therapeutics to minimize the treatment period and reducing the burden of drug-resistant Mtb and NTM infections are an urgent and pressing need. In our previous study, we identified anti-mycobacterial activity of orally bioavailable, non-cytotoxic, polycationic phosphorus dendrimer 2G0 against Mtb. In this study, we report ability of 2G0 to potentiate activity of multiple classes of antibiotics against drug-resistant mycobacterial strains. The observed synergy was confirmed using time-kill kinetics and revealed significantly potent activity of the combinations as compared to individual drugs alone. More importantly, no re-growth was observed in any tested combination. The identified combinations were further confirmed in intra-cellular killing assay as well as murine model of NTM infection, where 2G0 potentiated the activity of all tested antibiotics significantly better than individual drugs. Taken together, this nanoparticle with intrinsic antimycobacterial properties has the potential to represents an alternate drug candidate and/or a novel delivery agent for antibiotics of choice for enhancing the treatment of drug-resistant mycobacterial pathogens.

Ratiometric codelivery of Paclitaxel and Baicalein loaded nanoemulsion for enhancement of breast cancer treatment

The most prevalent clinical option for treating cancer is combination chemotherapy. In combination therapy, assessment and optimization for obtaining a synergistic ratio could be obtained by various preclinical setups. Currently, in vitro optimization is used to get synergistic cytotoxicity while constructing combinations. Herein, we co-encapsulated Paclitaxel (PTX) and Baicalein (BCLN) with TPP-TPGS1000 containing nanoemulsion (TPP-TPGS1000-PTX-BCLN-NE) for breast cancer treatment. The assessment of cytotoxicity of PTX and BCLN at different molar weight ratios provided an optimized synergistic ratio (1:5). Quality by Design (QbD) approach was later applied for the optimization as well as characterization of nanoformulation for its droplet size, zeta potential and drug content. TPP-TPGS1000-PTX-BCLN-NE significantly enhanced cellular ROS, cell cycle arrest, and depolarization of mitochondrial membrane potential in the 4T1 breast cancer cell line compared to other treatments. In the syngeneic 4T1 BALB/c tumor model, TPP-TPGS1000-PTX-BCLN-NE outperformed other nanoformulation treatments. The pharmacokinetic, biodistribution and live imaging studies pivoted TPP-TPGS1000-PTX-BCLN-NE enhanced bioavailability and PTX accumulation at tumor site. Later, histology studies confirmed nanoemulsion non-toxicity, expressing new opportunities and potential to treat breast cancer. These results suggested that current nanoformulation can be a potential therapeutic approach to effectively address breast cancer therapy.

Inhaled Adjunct Therapy with Second-Line Drug Candidates for Dose Reduction in Chemotherapeutic Regimens for Multi-drug-Resistant Tuberculosis

Chemotherapy of multi-drug-resistant tuberculosis (TB) requires prolonged administration of multiple drugs. We investigated whether pulmonary delivery of minute doses of drugs, along with reduced oral doses of the same agents, would affect preclinical efficacy. We prepared dry powder inhalation (DPI) formulations comprising sutezolid (SUT), the second-generation pretomanid analog TBA-354 (TBA), or a fluorinated derivative of TBA-354 (32,625) in a matrix of the biodegradable polymer poly(L-lactide). We established formulation characteristics, doses inhaled by healthy mice, and preclinical efficacy in a mouse model of TB. Oral doses of 100 mg/kg/day or DPI doses of 0.25-0.5 mg/kg/day of drugs SUT, TBA-354, or 32,625 administered over 28 days were sub-optimally effective in reducing lung and spleen burden of Mycobacterium tuberculosis (Mtb) in infected mice. The addition of 0.25-0.5 mg/kg/day of SUT, TBA-354, or 32,625 as DPI to oral doses of 50 mg/kg/day was non-inferior in clearing Mtb from the lungs of infected mice. We concluded that adjunct therapy with inhaled second-line agents has the potential to reduce the efficacious oral dose.

Enhanced apoptosis and mitochondrial cell death by paclitaxel-loaded TPP-TPGS1000-functionalized nanoemulsion

Background: The present research was designed to develop a nanoemulsion (NE) of triphenylphosphine-D-α-tocopheryl-polyethylene glycol succinate (TPP-TPGS₁₀₀₀) and paclitaxel (PTX) to effectively deliver PTX to improve breast cancer therapy. Materials & methods: A quality-by-design approach was applied for optimization and in vitro and in vivo characterization were performed. Results: The TPP-TPGS₁₀₀₀-PTX-NE enhanced cellular uptake, mitochondrial membrane depolarization and G₂M cell cycle arrest compared with free-PTX treatment. In addition, pharmacokinetics, biodistribution and in vivo live imaging studies in tumor-bearing mice showed that TPP-TPGS₁₀₀₀-PTX-NE had superior performance compared with free-PTX treatment. Histological and survival investigations ascertained the nontoxicity of the nanoformulation, suggesting new opportunities and potential to treat breast cancer. Conclusion: TPP-TPGS₁₀₀₀-PTX-NE improved the efficacy of breast cancer treatment by enhancing its effectiveness and decreasing drug toxicity.

Liquiritigenin, isoliquiritigenin rich extract of glycyrrhiza glabra roots attenuates inflammation in macrophages and collagen-induced arthritis in rats

Liquiritigenin (LTG) and its bioprecursor isoliquiritigenin(ISL), the main bioactives from roots of Glycyrrhiza genus are progressively documented as a potential pharmacological agent for the management of chronic diseases. The aim of this study was to evaluate the pharmacological potential of liquiritigenin, isoliquiritigenin rich extract of Glycyrrhiza glabra roots (IVT-21) against the production of pro-inflammatory cytokines from activated macrophages as well as further validated the efficacy in collagen-induced arthritis model in rats. We also performed the safety profile of IVT-21 using standard in-vitro and in-vivo assays. Results of this study revealed that the treatment of IVT-21 and its major bioactives (LTG, ISL) was able to reduce the production of pro-inflammatory cytokines (TNF-α, IL-6) in LPS-activated primary peritoneal macrophages in a dose-dependent manner compared with vehicle-alone treated cells without any cytotoxic effect on macrophages. In-vivo efficacy profile against collagen-induced arthritis in Rats revealed that oral administration of IVT-21 significantly reduced the arthritis index, arthritis score, inflammatory mediators level in serum. IVT-21 oral treatment is also able to reduce the NFкB-p65 expression as evidence of immunohistochemistry in knee joint tissue and mRNA level of pro-inflammatory cytokines in paw tissue in a dose-dependent manner when compared with vehicle treated rats. Acute oral toxicity profile of IVT-21 demonstrated that it is safe up to 2000 mg/kg body weight in experimental mice. This result suggests the suitability of IVT-21 for further study in the management of arthritis and related complications.

Pharmacological and Toxicological Study of Coumarinolignoids from Cleome viscosa in Small Animals for the Management of Rheumatoid Arthritis

This study aims to explore the possible pharmacological potential of Cleome viscosa Linn (Cleomaceae), an annual weed, into therapeutic value-added products. In the present study, we have explored the pharmacological and toxicological profile of coumarinolignoids isolated from Cleome viscose for the management of rheumatoid arthritis and related complications in a small animal model. To avoid the biasness during experiments on animals, we have coded the isolated coumarinolignoids as CLIV-92 to perform the experimental pharmacological study. CLIV-92 was orally administrated (30,100, 300 mg/kg) to animal models of collagen-induced arthritis (CIA), carrageenan-induced acute inflammation, thermal and chemical-induced pain, and Brewer's yeast-induced pyrexia. Oral administration of CLIV-92 significantly decreases the arthritis index, arthritis score, and increases the limb withdrawal threshold in the CIA model in experimental rats. The anti-arthritis studies revealed that the anti-inflammatory effect of CLIV-92 was associated with inhibition of the production of inflammatory mediators like TNF-α, IL-6, IL-17A, MMP-1, MMP-9, Nitric oxide, and C-RP in CIA rat's serum, and also reduced the NFкB-p65 expression as evidence of immunohistochemistry in knee joint tissue of CIA rats, in a dose-dependent manner. Further individual experiments related to arthritis-related complications in experimental animals demonstrated the analgesic, anti-inflammatory, and antipyretic potential of CLIV-92 in a dose-dependent manner. Further, an in-vivo acute oral toxicity study concluded that CLIV-92 is safe in experimental animals up to 2,000 mg/kg dose. The results of this study suggested that the oral administration of CLIV-92 may be a therapeutic candidate for further investigation in the management of rheumatoid arthritis and related complications.

Preparation and Evaluation of Low-Dose Calcitriol Dry Powder Inhalation as Host-Directed Adjunct Therapy for Tuberculosis

Background

It is unclear whether Vitamin D is efficacious as a host-directed therapy (HDT) for patients of tuberculosis (TB). We investigated pulmonary delivery of the active metabolite of Vitamin D₃, i.e., 1, 25-dihydroxy vitamin D₃ (calcitriol) in a mouse model of infection with Mycobacterium tuberculosis (Mtb).

Methods

We optimized a spray drying process to prepare a dry powder inhalation (DPI) of calcitriol using a Quality by Design (QbD) approach. We then compared outcomes when Mtb-infected mice were treated with inhaled calcitriol at 5 ng/kg as a stand-alone intervention versus DPI as adjunct to standard oral anti-tuberculosis therapy (ATT).

Results

The DPI with or without concomitant ATT markedly improved the morphology of the lungs and mitigated histopathology in both the lungs and the spleens. The number of nodular lesions on the lung surface decreased from 43.7 ± 3.1 to 22.5 ± 3.9 with the DPI alone and to 9.8 ± 2.5 with DPI + ATT. However, no statistically significant induction of host antimicrobial peptide cathelicidin or reduction in bacterial burden was seen with the DPI alone. DPI + ATT did not significantly reduce the bacterial burden in the lungs compared to ATT alone.

Conclusions

We concluded that HDT using the low dose calcitriol DPI contributed markedly to mitigation of pathology, but higher dose may be required to evoke significant induction of bactericidal host response and bactericidal activity in the lung.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11095-022-03360-5.

Accelerative Wound-Healing Effect of Aqueous Anthocephalus Cadamba Leaf Extract in a Diabetic Rat Model

Impaired wound healing is a major concern in diabetic patients due to unregulated chronic hyperglycemia which further may lead to ulcer, gangrene, and its complications. The present study unveils the accelerative effect of aqueous Anthocephalus cadamba leaf extract on wound healing in diabetic rats. Diabetes was induced in 30 Sprague Dawley female rats by using streptozotocin (except control group I) at the dose of 60 mg/kg intraperitoneally. Diabetic rats were randomized in 3 groups viz. diabetic control group (II), diabetes + Kadam plant leaf extract group (III), and diabetes + 5% povidone-iodine solution group (IV). Surgically sterile wound of 1.77 cm² was created on the dorsal area of anaesthetized rats. The experimental parameters were assessed by hematobiochemical, histopathological, and western blot techniques. The A cadamba extract treatment group (III) (D + KPLE) showed a significant increase in the percentage of wound closure (82%) at day 21 as compared to the diabetic control group (42%), nondiabetic control group (I) (49%), and povidone-iodine treatment group (75%) group (IV). The findings of the present study suggest that the (D + KPLE) group (III) exhibited marked epithelial regeneration, neovascularization, collagen deposition, and fibroblast proliferation along with higher expression of vascular endothelial growth factor as compared to the diabetic control group (II), which was confirmed by histopathological examination and western blot analysis. The present study suggests that the topical application of aqueous A cadamba leaf extract exhibits accelerative wound-healing properties in diabetic rats.

Self-Assembling Nano-Globular Peptide from Human Lactoferrin Acts as a Systemic Enhancer of Bone Regeneration: A Novel Peptide for Orthopedic Application

A technology for systemic and repeated administration of osteogenic factors for orthopedic use is an unmet medical need. Lactoferrin (∼80 kDa), present in milk, is known to support bone growth. We discovered a lactoferrin-mimetic peptide, LP2 (an 18-residue fragment from the N-terminus of the N-lobe of human lactoferrin), which self-assembles into a nano-globular assembly with a β-sheet structure in an aqueous environment. LP2 is non-hemolytic and non-cytotoxic against human red blood cells and 3T3 fibroblasts, respectively, and appreciably stable in the human serum. LP2 through the bone morphogenetic protein-dependent mechanism stimulates osteoblast differentiation more potently than the full-length protein as well as the osteoblastic production of osteoprotegerin (an anti-osteoclastogenic factor). Consequently, daily subcutaneous administration of LP2 to rats and rabbits with osteotomy resulted in faster bone healing and stimulated bone formation in rats with a low bone mass more potently than that with teriparatide, the standard-of-care osteogenic peptide for osteoporosis. LP2 has skeletal bioavailability and is safe at the 15× osteogenic dose. Thus, LP2 is a novel peptide that can be administered systemically for the medical management of hard-to-heal fractures.

Hesperidin-rich ethanol extract from waste peels of Citrus limetta mitigates rheumatoid arthritis and related complications

The aim of this study is to explore the possible pharmacological effects of fruit waste that may have a key role in converting the fruit waste into pharmaceutical agents. Citrus limetta (Rutaceae) is an important commercial citrus fruit crops used by juice processing industries. C. limetta peels are perishable waste material, which creates a big challenge in juice processing industries. Initial pharmaco-chemical profile of peels' extracts revealed that the ethanol extract (ClPs) has promising anti-inflammatory activity and rich in hesperidin content. In vivo experimental pharmacology profile of ClPs against arthritis and related complications revealed that oral administration of ClPs significantly reduced the arthritis score and arthritis index in elbow and knee joints against collagen-induced arthritis (CIA) in rats. Biochemical parameters include pro-inflammatory cytokines (TNF-α, IL-6, and IL-17A), and C-RP level in blood serum of CIA rats further confirmed the anti-arthritic profile of ClPs. Further individual experiments related to arthritis-related complications in experimental animals demonstrated the analgesic, anti-inflammatory, and antipyretic potential of ClPs in dose-dependent manner. The result of this study suggests the suitability of ClPs as a drug-like candidate for further investigation toward the management of arthritis and related complications.

Pancreastatin inhibitor PSTi8 protects the obesity associated skeletal muscle insulin resistance in diet induced streptozotocin-treated diabetic mice

Pancreastatin (PST), a chromogranin A (CHGA) derived peptide connects obesity with insulin resistance by inducing inflammation. Previously, we have evaluated potential activity of PST inhibitor (PSTi8) in liver and adipose tissue in type 2 diabetic mice model. In this study we further explore the therapeutic effect of PSTi8 on glucose metabolism in skeletal muscle cells/tissue and its effect on energy homeostasis in diet induced diabetic mice model. In in-vitro studies, we found that PSTi8 increases glucose uptake via enhanced GLUT4 translocation in L6 cells. This positive effect of PSTi8 led us to proceed with in-vivo studies in diabetic mice. C57BL/6 mice were fed HFD or HFrD diet for 12 weeks along with single STZ induction at 4th week followed by PSTi8 treatment. We found that HFD and HFrD model showed increased fat mass, caused glucose intolerance and insulin resistance, with accompanying proinflammatory effect on epididymal white adipose tissue (eWAT) together leading to skeletal muscle insulin resistance. Administration of PSTi8 protects from diet induced inflammatory response and enhances glucose tolerance and insulin sensitivity. PSTi8 improves circulating adipokine and lipid parameters, along with switch in macrophage polarisation from M1 to M2 in stromal vascular fraction of adipose tissue. In addition, treatment of PSTi8 also improves energy homeostasis, decreases circulatory non-esterified fatty acids level and inhibits ceramide deposition in muscle tissue. Overall this increased muscle insulin sensitivity is mediated via AKT/AS160/GLUT4 pathway activation. Our results reveal that PSTi8 inhibits the obesity mediated inflammation which enhances glucose disposal in skeletal muscle.