Unraveling novel roles of the Mycobacterium tuberculosis transcription factor Rv0081 in regulation of the nucleoid-associated proteins Lsr2 and EspR, cholesterol utilization, and subversion of lysosomal trafficking in macrophages.

The transcriptional network of Mycobacterium tuberculosis is designed to enable the organism to withstand host-associated stresses and to exploit the host milieu for its own survival and multiplication. Rv0081 (MT0088) is a transcriptional regulator whose interplay with other gene regulatory proteins and role in enabling M. tuberculosis to thrive within its host is incompletely understood. M. tuberculosis utilizes cholesterol within the granuloma. We show that deletion of Rv0081 compromises the ability of M. tuberculosis to utilize cholesterol as the sole carbon source, to subvert lysosomal trafficking, and to form granulomas in vitro. Rv0081 downregulates expression of the nucleoid-associated repressor Lsr2, leading to increased expression of the cholesterol catabolism-linked gene kshA and genes of the cholesterol importing operon, accounting for the requirement of Rv0081 in cholesterol utilization. Furthermore, Rv0081 activates EspR which is required for secretion of ESX-1 substrates, which in turn are involved in subversion of lysosomal trafficking of M. tuberculosis and granuloma expansion. These results provide new insight into the role of Rv0081 under conditions which resemble the environment encountered by M. tuberculosis within its host. Rv0081 emerges as a central regulator of genes linked to various pathways which are crucial for the survival of the bacterium in vivo.

Sialic Acid Engineered Prodrug Nanoparticles for Codelivery of Bortezomib and Selenium in Tumor Bearing Mice.

Most cancer patients rarely benefit from monodrug therapy because of both cancer complexity and tumor environment. One of the main reasons for this failure is insufficient accumulation of the optimal dose at the tumorous site. Our investigation implies a promising strategy to engineer prodrug nanoparticles (NPs) of bortezomib (BTZ) and selenium (Se) using sialic acid (SAL) as a ligand to improve breast cancer therapy. BTZ was conjugated with SAL and HPMA (N-2-hydroxypropyl methacrylamide) to prepare a prodrug conjugate; BTZ-SAL-HPMA (BSAL-HP) and then fabricated into prodrug NPs with Se (Se_BSAL-HP prodrug NPs). The self-assembly of prodrug NPs functionalized with Se showed size (204.13 ± 0.02 nm) and zeta potential (-31.0 ± 0.11 mV) in dynamic light scattering (DLS) experiments and spherical shape in TEM and SEM analysis. Good stability and low pH drug release profile were characterized by Se_BSAL-HP prodrug NPs. The tumor-selective boronate-ester-based prodrug NPs of BTZ in combination with Se endowed a synergistic effect against cancer cells. Compared to prodrug conjugate, Se_BSAL-HP prodrug NPs exhibited higher cell cytotoxicity and enhanced cellular internalization with significant changes in mitochondria membrane potential (MMP). Elevated apoptosis was observed in the (G2/M) phase of the cell cycle for Se_BSAL-HP prodrug NPs (2.7-fold) higher than BTZ. In vivo studies were performed on Sprague-Dawley rats and resulted in positive trends. The increased therapeutic activity of Se_BSAL-HP prodrug NPs inhibited primary tumor growth and showed 43.05 fold decrease in tumor volume than the control in 4T1 tumor bearing mice. The surprising and remarkable outcomes for Se_BSAL-HP prodrug NPs were probably due to the ROS triggering effect of boronate ester and selenium given together.

N-2-Hydroxypropylmethacrylamide-Polycaprolactone Polymeric Micelles in Co-delivery of Proteasome Inhibitor and Polyphenol: Exploration of Synergism or Antagonism.

Breast cancer leads to the highest mortality among women resulting in a major clinical burden. Multidrug therapy is more efficient in such patients compared to monodrug therapy. Simultaneous combinatorial or co-delivery garnered significant interest in the past years. Caffeic acid (CFA) (a natural polyphenol) has received growing attention because of its anticarcinogenic and antioxidant potential. Bortezomib (BTZ) is a proteasome inhibitor and may be explored for treating breast cancer. Despite its high anticancer activity, the low water solubility and chemical instability restrict its efficacy against solid tumors. In the present study, we designed and investigated a HP-PCL (N-2-hydroxypropylmethacrylamide-polycaprolactone) polymeric micellar (PMCs) system for the simultaneous delivery of BTZ and CFA in the treatment of breast cancer. The designed BTZ+CFA-HP-PCL PMCs were fabricated, optimized, and characterized for size, zeta potential, surface morphology, and in vitro drug release. Developed nanosized (174.6 ± 0.24 nm) PMCs showed enhanced cellular internalization and cell cytotoxicity in both MCF-7 and MDA-MB-231 cells. ROS (reactive oxygen species) levels were highest in BTZ-HP-PCL PMCs, while CFA-HP-PCL PMCs significantly (p < 0.001) scavenged the ROS generated in 2',7'-dichlorofluorescein diacetate (DCFH-DA) assay. The mitochondrial membrane potential (MMP) assay revealed intense and significant green fluorescence in both types of cancer cells when treated with BTZ-HP-PCL PMCs (p < 0.001) indicating apoptosis or cell death. The pharmacokinetic studies revealed that BTZ-HP-PCL PMCs and BTZ+CFA-HP-PCL PMCs exhibited the highest bioavailability, enhanced plasma half-life, decreased volume of distribution, and lower clearance rate than the pure combination of drugs. In the organ biodistribution studies, the combination of BTZ+CFA showed higher distribution in the spleen and the heart. Overall findings of in vitro studies surprisingly resulted in better therapeutic efficiency of BTZ-HP-PCL PMCs than BTZ+CFA-HP-PCL PMCs. However, the in vivo tumor growth inhibition study performed in tumor-induced mice concluded that the tumor growth was inhibited by both BTZ-HP-PCL PMCs and BTZ+CFA-HP-PCL PMCs (p < 0.0001) more efficiently than pure BTZ and the combination (BTZ+CFA), which may be due to the conversion of boronate ester into boronic acid. Henceforth, the combination of BTZ and CFA provides further indications to be explored in the future to support the hypothesis that BTZ may work with polyphenol (CFA) in the acidic environment of the tumor.

Lipid-Based Nanocarriers in the Treatment of Glioblastoma Multiforme (GBM): Challenges and Opportunities.

Glioblastoma multiforme (also known as glioblastoma; GBM) is one of the most malignant types of brain tumors that occurs in the CNS. Treatment strategies for glioblastoma are majorly comprised of surgical resection, radiotherapy, and chemotherapy along with combination therapy. Treatment of GBM is itself a tedious task but the involved barriers in GBM are one of the main impediments to move one step closer to the treatment of GBM. Basically, two of the barriers are of utmost importance in this regard, namely blood brain barrier (BBB) and blood brain tumor barrier (BBTB). This review will address different challenges and barriers in the treatment of GBM along with their etiology. The role and recent progress of lipid-based nanocarriers like liposomes, solid lipid nanocarriers (SLNs), nanostructured lipid carriers (NLCs), lipoplexes, and lipid hybrid carriers in the effective management of GBM will be discussed in detail.

Desidustat in Anemia due to Dialysis-Dependent Chronic Kidney Disease: A Phase 3 Study (DREAM-D).

BACKGROUND: A phase 3 study to assess the efficacy and safety of the desidustat, an oral hypoxia-inducible factor prolyl hydroxylase inhibitor, against the epoetin alfa for the treatment of anemia in patients with chronic kidney disease (CKD) with dialysis dependency. METHODS: DREAM-D was a phase 3, multicenter, open-label, randomized, active-controlled clinical study conducted across 38 centers in India. A total of 392 patients with clinical diagnosis of anemia due to CKD with dialysis need (Erythrocyte Stimulating Agent [ESA] naïve or prior ESA users) and with baseline hemoglobin levels of 8.0-11.0 g/dL (inclusive) were randomized in a 1:1 ratio to receive either desidustat oral tablets (thrice a week) or epoetin alfa subcutaneous injection for 24 weeks to maintain a hemoglobin level of 10-12 g/dL. The primary endpoint was to assess the change in the hemoglobin level between the desidustat and the epoetin alfa groups from the baseline to evaluation period week 16-24. The key secondary efficacy endpoint was the number of patients with hemoglobin response. RESULTS: The least square mean (standard error) change in hemoglobin from the baseline to week 16-24 was 0.95 (0.09) g/dL in the desidustat group and 0.80 (0.09) g/dL in the epoetin alfa group (difference: 0.14 [0.14] g/dL; 95% confidence interval: -0.1304, 0.4202), which met the prespecified noninferiority margin. The number of hemoglobin responders was significantly higher in the desidustat group (106 [59.22%]) when compared to the epoetin alfa group (89 [48.37%]) (p = 0.0382). The safety profile of the desidustat oral tablet was comparable with the epoetin alfa injection. There were no new risks or no increased risks seen with the use of desidustat compared to epoetin alfa. CONCLUSION: In this study, desidustat was found to be noninferior to epoetin in the treatment of anemia in CKD patients on dialysis and it was well-tolerated. Clinical Trial Registry Identifier: CTRI/2019/12/022312 (India).

Long-term experience with a modified ERAS protocol for urogynaecology day procedures.

Enhanced recovery after surgery (ERAS) protocols were first reported for colorectal and gynaecologic procedures. The main benefits have been a shorter length of stay and reduced complications. A retrospective audit was conducted of all patients who underwent ambulatory pelvic organ prolapse surgery at the Townsville Day Surgery between January 2008 and June 2019. Following the publication of a former audit, a modified ERAS protocol was adopted at our practice. We omitted a carbohydrate-rich fluid intake prior to surgery in our local protocol. Data were analysed for the type of surgery, postoperative complications, and readmissions. All surgeries were performed by a single consultant urogynecologist. A total of 1381 women underwent 1937 surgeries. Transvaginal mesh (55.8%) was the commonest procedure, followed by a posterior repair (23.9%). Ninety-five patients (4.4%) had various complications, with a failed trial of the void as the commonest complication (87 patients). Only 8 patients (0.4%) required an unplanned admission after their procedures. Site-specific ERAS protocol is effective for providing standardised care in the surgical treatment of women with pelvic organ prolapse and urinary incontinence in an outpatient setting. Complication rates are low and reduce further with experience and familiarity with the protocol.Impact statement:What is already known on this subject? Enhanced recovery after surgery (ERAS) protocols are being increasingly used in surgical practices. The main objective of the protocol has been on reducing postoperative morbidity and stay. The commonly practiced protocol includes a high protein intake diet and a glucose drink prior to surgery.What do the results of this study add? Our study utilises a modified ERAS protocol of omitting the high protein diet and the glucose drink for the minimally invasive uro-gynaecology procedures. The modified protocol is safe and associated with lower complications and readmission rates.What are the implications of these findings for clinical practice and/or further research? The present study demonstrates the safety and effectiveness of our modified ERAS protocol that allows for patients to undergo surgical procedures and discharge on the same day, thus minimising the impact on the quality of life and vocations. A multi-center randomised controlled trial will conclusively demonstrate a cause-effect relationship between early discharge and patient preparation with our modification of the ERAS protocol. Further research should also consider patient satisfaction as an additional outcome measure.

Improved Mycobacterium tuberculosis clearance after the restoration of IFN-γ+ TNF-α+ CD4+ T cells: Impact of PD-1 inhibition in active tuberculosis patients.

Prolonged therapy, drug toxicity, noncompliance, immune suppression, and alarming emergence of drug resistance necessitate the search for therapeutic vaccine strategies for tuberculosis (TB). Such strategies ought to elicit not only IFN-γ, but polyfunctional response including TNF-α, which is essential for protective granuloma formation. Here, we investigated the impact of PD-1 inhibition in facilitating protective polyfunctional T cells (PFTs), bacillary clearance, and disease resolution. We have observed PD-1 inhibition preferentially rescued the suppressed PFTs in active tuberculosis patients. In addition, polyfunctional cytokine milieu favored apoptosis of infected MDMs over necrosis with markedly reduced bacillary growth (≪CFU) in our in vitro monocyte-derived macrophages (MDMs) infection model. Furthermore, the animal study revealed a significant decline in the bacterial burden in the lungs and spleen of infected mice after in vivo administration of α-PD-1 along with antitubercular treatment. Our findings suggest that rescuing polyfunctional immune response by PD-1 inhibition works synergistically with antituberculosis chemotherapy to confer improved control over bacillary growth and dissemination. In summary, our data strongly indicate the therapeutic potential of α-PD-1 as adjunct immunotherapy that can rejuvenate suppressed host immunity and enhance the efficacy of candidate therapeutic vaccine(s).

Activating transcription factor 3 modulates the macrophage immune response to Mycobacterium tuberculosis infection via reciprocal regulation of inflammatory genes and lipid body formation.

Infection of macrophages by Mycobacterium tuberculosis elicits an immune response that clears the bacterium. However, the bacterium is able to subvert the innate immune response. Differential expression of transcription factors (TFs) is central to the dynamic balance of this interaction. Among other functions, TFs regulate the production of antibacterial agents such as nitric oxide, pro-inflammatory cytokines and neutral lipids which are stored in lipid bodies (LBs) and favour bacterial survival. Here, we demonstrate that the TF activating transcription factor 3 (ATF3) is upregulated early during infection of macrophages or mice. Depletion of ATF3 enhances mycobacterial survival in macrophages suggesting its host-protective role. ATF3 interacts with chromatin remodelling protein brahma-related gene 1 and both associate with the promoters of interleukin-12p40, interleukin-6 and nitric oxide synthase 2, to activate expression of these genes. Strikingly, ATF3 downregulates LB formation by associating at the promoters of positive regulators of LB formation such as cholesterol 25 hydroxylase and the microRNA-33 locus. ATF3 represses the association of the activating mark, acetyl histone H4 lysine 8 at the promoter of cholesterol 25 hydroxylase. Our study suggests opposing roles of ATF3 in regulation of distinct sets of macrophage genes during infection, converging on a host-protective immune response.

Phosphatase-defective DevS sensor kinase mutants permit constitutive expression of DevR-regulated dormancy genes in Mycobacterium tuberculosis.

The DevR-DevS/DosR-DosS two-component system of Mycobacterium tuberculosis, that comprises of DevS sensor kinase and DevR response regulator, is essential for bacterial adaptation to hypoxia by inducing dormancy regulon expression. The dominant phosphatase activity of DevS under aerobic conditions enables tight negative control, whereas its kinase function activates DevR under hypoxia to induce the dormancy regulon. A net balance in these opposing kinase and phosphatase activities of DevS calibrates the response output of DevR. To gain mechanistic insights into the kinase-phosphatase balance of DevS, we generated alanine substitution mutants of five residues located in DHp α1 helix of DevS, namely Phe-403, Gly-406, Leu-407, Gly-411 and His-415. For the first time, we have identified kinase positive phosphatase negative (K+P-) mutants in DevS by a single-site mutation in either Gly-406 or Leu-407. M. tuberculosis Gly-406A and Leu-407A mutant strains constitutively expressed the DevR regulon under aerobic conditions despite the presence of negative signal, oxygen. These mutant proteins exhibited ∼2-fold interaction defect with DevR. We conclude that Gly-406 and Leu-407 residues are individually essential for the phosphatase function of DevS. Our study provides new insights into the negative control mechanism of DevS by demonstrating the importance of an optimal interaction between DevR and DevS, and local changes associated with individual residues, Gly-406 and Leu-407, which mimic ligand-free DevS. These K+P- mutant strains are expected to facilitate the rapid aerobic screening of DevR antagonists in M. tuberculosis, thereby eliminating the requirement for hypoxic culture conditions.

Sialic Acid Conjugated Chitosan Nanoparticles: Modulation to Target Tumour Cells and Therapeutic Opportunities.

Targeted delivery of therapeutics forestalls the dreadful delocalized effects, drug toxicities and needless immunosuppression. Cancer cells are bounteous with sialic acid and the differential expression of glycosyl transferase, glycosidase and monosaccharide transporter compared to healthy tissues. The current study entails the development and characterisation of sialic acid (SA)-labelled chitosan nanoparticles encapsulating gemcitabine (GEM). Chitosan (CS) was conjugated with SA using coupling reaction and characterised spectroscopically. Furthermore, different concentrations of chitosan and tripolyphosphate (TPP) were optimised to fabricate surface modified chitosan nanoparticles. SA conjugated chitosan nanoparticles encapsulating GEM (SA-CS_GEM NPs) of 232 ± 9.69 nm with narrow distribution (PDI < 0.5) and zeta potential of - 19 ± 0.97 mV was fabricated. GEM was successfully loaded in the SA-CS NPs, depicting prolonged and biphasic drug release pattern more elated at low pH. Pronounced cellular uptake (FITC tagged) and cytotoxicity (IC50 487.4 nM) was observed in SA-CS_GEM NPs against A549 cells. IC50 for SA-CS_GEM NPs plunged with an increase in the time points from 24 to 72 h. Concentration-dependent haemolytic study confirmed significant haemocompatibility of SA-CS_GEM NPs. Pharmacokinetic study was performed on Sprague-Dawley rats and the kinetic parameters were calculated using PKSolver 2.0. Results demonstrated a consequential refinement of 2.98 times in modified SA-CS_GEM NPs with a significant increase in retention time, bioavailability and elimination half-life, and decrease in elimination rate constant and volume of distribution in comparison to CS_GEM NPs. Therefore, SA-CS shell core nanoparticles could be a beneficial approach to target and treat NSCLC (non-small cell lung cancer) and direct for research possibilities to target the other tumour cells.

The sensor kinase MtrB of Mycobacterium tuberculosis regulates hypoxic survival and establishment of infection.

Paired two-component systems (TCSs), having a sensor kinase (SK) and a cognate response regulator (RR), enable the human pathogen Mycobacterium tuberculosis to respond to the external environment and to persist within its host. Here, we inactivated the SK gene of the TCS MtrAB, mtrB, generating the strain ΔmtrB We show that mtrB loss reduces the bacterium's ability to survive in macrophages and increases its association with autophagosomes and autolysosomes. Notably, the ΔmtrB strain was markedly defective in establishing lung infection in mice, with no detectable lung pathology following aerosol challenge. ΔmtrB was less able to withstand hypoxic and acid stresses and to form biofilms and had decreased viability under hypoxia. Transcriptional profiling of ΔmtrB by gene microarray analysis, validated by quantitative RT-PCR, indicated down-regulation of the hypoxia-associated dosR regulon, as well as genes associated with other pathways linked to adaptation of M. tuberculosis to the host environment. Using in vitro biochemical assays, we demonstrate that MtrB interacts with DosR (a noncognate RR) in a phosphorylation-independent manner. Electrophoretic mobility shift assays revealed that MtrB enhances the binding of DosR to the hspX promoter, suggesting an unexpected role of MtrB in DosR-regulated gene expression in M. tuberculosis Taken together, these findings indicate that MtrB functions as a regulator of DosR-dependent gene expression and in the adaptation of M. tuberculosis to hypoxia and the host environment. We propose that MtrB may be exploited as a chemotherapeutic target against tuberculosis.

Diversity of Spectrum and Management of Animal-Inflicted Injuries in the Pediatric Age Group: A Prospective Study from a Pediatric Surgery Department Catering Primarily to the Rural Population.

INTRODUCTION: Animal-inflicted injuries continue to be a major health problem worldwide. In developing countries, the outcome of such injuries, especially in children may be poor. AIM: The study aimed to evaluate the diversity of spectrum and management of animal-inflicted injuries in the pediatric age group. MATERIALS AND METHODS: This was a prospective study on animal-inflicted injuries in children between 1 to 15 years of age over a period of 12 months. Data on various parameters such as age and sex, animal species involved, provoked/unprovoked, mechanism of injury, time of injury, prehospital care, injury-arrival interval, pattern and type of injury, trauma score, body region injured, treatment given and complications were collected and analyzed. RESULTS: Fifty-two children with animal-inflicted injuries were included, constituting <1% of all trauma cases seen during the study period (male:female = 2:1). The mean age of the cohort was 9.65 years. Domestic animals were responsible in 41 children (78.84%) and wild animals in 11 children (21.16%). Dog bite was the most common (57.69%). Penetrating injury was observed in 40 (76.9%) and blunt injury was observed in 12 (23.1%). The musculoskeletal system was the most common organ-system injured affecting 36 children (69.23%). Thirty-five children (67.3%) after minor treatment were discharged. Seventeen children (32.7%) required admission. Thirty-four children (65.38%) underwent surgical procedures. Wound debridement was the most common procedure performed. Wound infection was observed in 20 children (38.46%) and was significantly higher (P < 0.01) in delayed presenters. The length of hospital stay for the admitted children ranged from 3 to 28 days. CONCLUSION: Animal-inflicted injuries are rare in children and have a wide spectrum of presentation. Severe injuries require extensive resuscitation and expert surgical care. Mild injuries can be managed conservatively with the use of proper dressings, antibiotics, and analgesics.

MicroRNA 26a (miR-26a)/KLF4 and CREB-C/EBPß regulate innate immune signaling, the polarization of macrophages and the trafficking of Mycobacterium tuberculosis to lysosomes during infection.

For efficient clearance of Mycobacterium tuberculosis (Mtb), macrophages tilt towards M1 polarization leading to the activation of transcription factors associated with the production of antibacterial effector molecules such as nitric oxide (NO) and proinflammatory cytokines such as interleukin 1 ß (IL-1ß) and tumor necrosis factor α (TNF-α). At the same time, resolution of inflammation is associated with M2 polarization with increased production of arginase and cytokines such as IL-10. The transcriptional and post-transcriptional mechanisms that govern the balance between M1 and M2 polarization, and bacteria-containing processes such as autophagy and trafficking of Mtb to lysosomes, are incompletely understood. Here we report for the first time, that the transcription factor KLF4 is targeted by microRNA-26a (miR-26a). During Mtb infection, downregulation of miR-26a (observed both ex vivo and in vivo) facilitates upregulation of KLF4 which in turn favors increased arginase and decreased iNOS activity. We further demonstrate that KLF4 prevents trafficking of Mtb to lysosomes. The CREB-C/EBPß signaling axis also favors M2 polarization. Downregulation of miR-26a and upregulation of C/ebpbeta were observed both in infected macrophages as well as in infected mice. Knockdown of C/ebpbeta repressed the expression of selected M2 markers such as Il10 and Irf4 in infected macrophages. The importance of these pathways is substantiated by observations that expression of miR-26a mimic or knockdown of Klf4 or Creb or C/ebpbeta, attenuated the survival of Mtb in macrophages. Taken together, our results attribute crucial roles for the miR-26a/KLF4 and CREB-C/EBPßsignaling pathways in regulating the survival of Mtb in macrophages. These studies expand our understanding of how Mtb hijacks host signaling pathways to survive in macrophages, and open up new exploratory avenues for host-targeted interventions.

Lactoferrin Coupled Lower Generation PAMAM Dendrimers for Brain Targeted Delivery of Memantine in Aluminum-Chloride-Induced Alzheimer's Disease in Mice.

Lower generation PAMAM dendrimers have an immense potential for drug delivery with lower toxicity, but these dendrimers yet need certain basic ameliorations. In this study, the brain delivery potential of the synthesized PAMAM-Lf (lower generation PAMAM and lactoferrin conjugate) loaded with memantine (MEM) was explored and evaluated in vitro and in vivo in the disease-induced mouse model. The developed nanoscaffolds were characterized for size, zeta potential and in vitro release. Increase in the average size from 11.54 ± 0.91 to 131.72 ± 4.73 nm, respectively, was observed for drug-loaded PAMAM (i.e., PAMAM-MEM) and PAMAM-Lf (i.e., MEM-PAMAM-Lf).  Release profile of MEM from MEM-PAMAM-Lf was slow and sustained up to 48 h. In vivo biodistribution in the Sprague-Dawley rat model revealed that the brain uptake of MEM-PAMAM-Lf was significantly higher than that of MEM alone. The behavioral response study in the healthy rats did not result in any significant changes. The in vivo study in an AlCl3-induced Alzheimer's (AD) mice model showed a significant improvement in behavioral responses. Optical density, which reflects the acetylcholinesterase (AChE) activity, was highest in the AL group 0.16 ± 0.01 (higher than the CON group, 0.09 ± 0.02; p < 0.05). No significant suppression of AChE activity was recorded in all the other treated groups. Similarly, the DOPAmine and 3,4 dihydroxyphenylacetic acid (DOPAC) levels were unaffected by the developed formulations. The study reported improved brain bioavailability of MEM in AlCl3-induced Alzheimer's mice leading to improved memory, with the resultant mechanism behind in a descriptive manner. This study is among the preliminary studies reporting the memory improvement aspect of PAMAM-Lf conjugates for MEM in AlCl3-AD induced mice. The formulation developed was beneficial in AD-induced mice and had a significant impact on the memory aspects.

Glycine-Poly-L-Lactic Acid Copolymeric Nanoparticles for the Efficient Delivery of Bortezomib.

PURPOSE: Bortezomib (BTZ) is a proteasome inhibitor used for multiple myeloma and mantle cell lymphoma treatment. BTZ's aqueous in solubility is the main hindrance in its successful development as a commercial formulation. The main objective of the present study is to develop and characterize folic acid-glycine-poly-L-lactic acid (FA-Gly4-PLA) based nanoformulation (NPs) to improve solubility and efficacy of BTZ. METHODS: BTZ loaded FA-Gly4-PLA NPs were prepared and characterized for size, zeta potential, in vitro studies such as release, kinetics modeling, hemolytic toxicity, and cell line-based studies (Reactive Oxygen Species: ROS and cytotoxicity). RESULTS: BTZ loaded NPs (BTZ-loaded FA-Gly4-PLA) and blank NPs (FA-Gly4-PLA) size, zeta, and PDI were found to be 110 ± 8.1 nm, 13.7 ± 1.01 mV, 0.19 ± 0.03 and 198 ± 9.01 nm, 8.63 ± 0.21 mV, 0.21 ± 0.08 respectively. The percent encapsulation efficiency (% EE) and percent drug loading (% DL) of BTZ loaded FA-Gly4-PLA NPs was calculated to be 78.3 ± 4.1 and 12.38 ± 2.1. The Scanning Electron Microscopy (SEM) showed that NPs were slightly biconcave in shape. The in vitro release of BTZ from FA-Gly4-PLA NPs resulted in the sustained manner. The prepared NPs were less hemolytic than BTZ. CONCLUSIONS: BTZ loaded Gly4-PLA NPs apoptotic index was found to be much higher than BTZ but lesser than BTZ loaded FA-Gly4-PLA against breast cancer cell lines (MDA-MB-231). ROS intracellular assessment assay indicated that BTZ and BTZ loaded FA-Gly4-PLA NPs exhibited higher ROS production. Conclusively, the BTZ loaded FA-Gly4-PLA NPs were able to encapsulate more BTZ than BTZ loaded Gly4-PLA NPs and were found to be more effective as per as in vitro anti-cancer effect is concerned.

Nano-Co-Delivery of Berberine and Anticancer Drug Using PLGA Nanoparticles: Exploration of Better Anticancer Activity and In Vivo Kinetics.

PURPOSE: Combinatorial approach can be beneficial for cancer treatment with better patient recovery. Co-delivery of natural and synthetic anticancer drug not only valuable to achieve better anticancer effectivity but also to ascertain toxicity. This study was aimed to co-deliver berberine (natural origin) and doxorubicin (synthetic origin) utilizing conjugation/encapsulation strategy through poly (lactic-co-glycolic acid) (PLGA) nanoparticles. METHODS: Doxorubicin was efficiently conjugated to PLGA via carbodiimide chemistry and the PLGA-doxorubicin conjugate (PDC) was used for encapsulation of berberine (PDBNP). RESULTS: Significant anti-proliferative against MDA-MB-231 and T47D breast cancer cell lines were observed with IC50 of 1.94 ± 0.22 and 1.02 ± 0.36 µM, which was significantly better than both the bio-actives (p < 0.05). The ROS study revealed that the PDBNP portrayed the slight increase in the reactive oxygen species (ROS) pattern in MDA-MB-231 cell line in a dose-dependent manner, while in T47D cells, no significant change in ROS was seen. PDBNP exhibits significant alteration (depolarization) in mitochondrial membrane permeability and arrest of cell cycle progression at sub G1 phase while the Annexin V/PI assay followed by confocal microscopy resulted into cell death mode to be because of necrosis against MDA-MB-231 cells. In vivo studies in Sprague Dawley rats revealed almost 14-fold increase in half life and a significant increase in plasma drug concentration. CONCLUSION: The overall approach of PLGA based co-delivery of doxorubicin and berberine witnessed synergetic effect and reduced toxicity as evidenced by preliminary toxicity studies.

Inhalable liposomes of Glycyrrhiza glabra extract for use in tuberculosis: formulation, in vitro characterization, in vivo lung deposition, and in vivo pharmacodynamic studies.

OBJECTIVE: The current study involves the development of liposomal dry powder for inhalation (LDPI) containing licorice extract (LE) for use in tuberculosis. SIGNIFICANCE: The current epidemiology of tuberculosis along with the increasing emergence of resistant forms of tuberculosis necessitates the need for developing alternative efficacious medicines for treatment. Licorice is a medicinal herb with reported activity against Mycobacterium tuberculosis. METHODS: Liposomes with LE were prepared by thin film hydration technique and freeze dried to obtain LDPI. The comprehensive in vitro and in vivo characterization of the LDPI formulation was carried out. RESULTS: The particle size of liposomes was around 210 nm with drug entrapment of almost 75%. Transmission electron microscopy revealed spherical shape of liposome vesicles. The flow properties of the LDPI were within acceptable limits. Anderson Cascade Impactor studies showed the mean median aerodynamic diameter, geometric standard deviation and fine particle fraction of the LDPI to be 4.29 µm, 1.23, and 54.68%, respectively. In vivo lung deposition studies of LDPI in mice showed that almost 46% of the drug administered reaches the lungs and 16% of administered drug is retained in the lungs after 24 hours of administration. The in vivo pharmacodynamic evaluation of the LDPI showed significant reduction in bacterial counts in lungs as well as spleen of TB-infected mice. CONCLUSIONS: LE LDPI thus has a promising potential to be explored as an effective anti-tubercular medicine or as an adjunct to existing anti-tubercular drugs.

Self-Emulsifying Oral Lipid Drug Delivery Systems: Advances and Challenges.

The attempts to oral delivery of lipids can be challenging. Self-emulsifying drug delivery system (SEDDS) plays a vital role to tackle this problem. SEDDS is composed of an oil phase, surfactants, co-surfactants, emulsifying agents, and co-solvents. SEDDS can be categorized into self-nano-emulsifying agents (SNEDDS) and self-micro-emulsifying agents (SMEDDS). The characterization of SEDDS includes size, zeta potential analysis, and surface morphology via electron microscopy and phase separation methods. SEDDS can be well characterized through different techniques for size and morphology. Supersaturation is the phenomenon applied in case of SEDDS, in which polymers and copolymers are used for SEDDS preparation. A supersaturated SEDDS formulation kinetically and thermodynamically inhibits the precipitation of drug molecules by retarding nucleation and crystal growth in the aqueous medium. Self-emulsification approach has been successful in the delivery of anti-cancer agents, anti-viral drugs, anti-bacterial, immunosuppressant, and natural products such as antioxidants as well as alkaloids. At present, more than four SEDDS drug products are available in the market. SEDDS have tremendous capabilities which are yet to be explored which would be beneficial in oral lipid delivery.

Boosted Memory and Improved Brain Bioavailability of Rivastigmine: Targeting Effort to the Brain Using Covalently Tethered Lower Generation PAMAM Dendrimers with Lactoferrin.

Currently, there is no treatment strategy which can reverse the process of neuro-degeneration in progression of Alzheimer's disease (AD). Practically, it is desired to achieve and maintain high therapeutic doses in the brain, but it is hard due to selective permeability of the blood-brain barrier (BBB). In the present study, lactoferrin (Lf) was conjugated to polyamidoamine generation 3.0 (PAMAM G3.0) dendrimers for the effective delivery of rivastigmine (RIV) to the brain. Conjugation of PAMAM G3.0 with lactoferrin was confirmed by FT-IR, 1H NMR, and 2D-NMR spectroscopy as well as AFM techniques. Further, RIV was loaded into PAMAM G3.0 and PAMAM-Lf conjugates. RP-HPLC was used to quantify the drug loading and release as well. Spectroscopic analysis confirmed PAMAM-Lf conjugation, the size of the conjugate was 100.04 ± 3.1 nm, and after RIV loading, the size was increased up to 216.13 ± 2.3 nm. Atomic force microscopic results revealed that the root-mean-square roughness ( Rq) and surface roughness ( Ra) were 6.31 and 5.27 nm, respectively, along with other parameters, Skewness and Kurtosis, which were 0.522 and 2.50, respectively. In vitro drug release from the PAMAM-Lf-RIV conjugate was sustained up to more than 100 h, and that of naive RIV was quite rapid (approxmately 99% release was observed in 8 h). Ex vivo hemotoxicity of the PAMAM-Lf-RIV conjugate was almost 9.8-fold lesser than the PAMAM G3.0 ( p < 0.0001), 7.77 times that of PAMAM-enc-RIV and 5 times that of naïve RIV ( p < 0.0001), respectively. The in vivo targeting potency of the conjugate was investigated in a rat model. Bioavailability of the RIV was enhanced 7.87 times compared to RIV along with improved pharmacokinetic parameters. Brain uptake of the drug was improved when treated with PAMAM-Lf-RIV over the RIV and PAMAM-enc-RIV, almost 8 and 4.2 times, respectively, after 4 h of the administration. Additionally, the behavioral studies revealed that PAMAM-Lf-RIV significantly enhanced the overall locomotor activity with higher ambulations over the pure drug and PAMAM-enc-RIV formulation. The outcome of the novel object recognition test was an indirect evidence of memory improvement. Conclusively, the development and characterization of PAMAM-Lf-RIV resulted in improved brain uptake and brain bioavailability with boosted memory, which can be beneficial in the treatment of Alzheimer's.

Bendamustine-PAMAM Conjugates for Improved Apoptosis, Efficacy, and in Vivo Pharmacokinetics: A Sustainable Delivery Tactic.

Successful delivery of a chemotherapeutic agent like bendamustine still remains a challenge in clinical conditions like chronic lymphatic leukemia (CLL), non-Hodgkin lymphoma (NHL), and multiple myeloma. We have conjugated bendamustine to polyamidoamine (PAMAM) dendrimers after conjugating with N-(hydroxyethyl)maleimide (spacer) via an ester bond. The particle size of PAMAM-bendamustine conjugate was 49.8 ± 2.5 nm. In vitro drug release resulted in sustained release with improved solution stability of drug up to 72 h. In a 24 h cytotoxicity study by MTT assay against human monoblastic leukemia cells (THP-1), the IC50 value for PAMAM-bendamustine was 32.1 ± 4.8 µM compared to 50.42 ± 3.4 µM and 2303 ± 106.5 µM for bendamustine and PAMAM dendrimer, respectively. Significantly higher cell uptake and apoptosis were observed in THP-1 cells by PAMAM-bendamustine conjugate which was confirmed by flow cytometry and confocal laser scanning microscopy. Preliminary in vivo studies undertaken included pharmacokinetics studies, organ distribution studies, and tumor inhibition studies. In healthy Wistar rat model (1CBM IV push model), the pharmacokinetic studies revealed that bioavailability and t1/2 increased significantly, i.e., almost 8.5-fold (193.8 ± 1.116 vs 22.8 ± 0.158 µg mL-1/h) and 5.1-fold (0.75 ± 0.005 vs 3.85 ± 0.015 h), respectively, for PAMAM-bendamustine conjugate compared to pure bendamustine ( p < 0.05), however, clearance and volume of distribution were found to be decreased compared to those of free drug. The study suggests that PAMAM-bendamustine conjugate was not only stable for the longer period but also least toxic and highly taken up by THP-1 cells to exert an anticancer effect at the reduced dose. Tumor inhibition and biodistribution studies in tumor-bearing BALB/c mice revealed that PAMAM-bendamustine conjugate was more effective than the pure drug and showed higher accumulation in the tumor.