Bahman Khameneh

Postbiotics, bioactive metabolites produced by probiotic bacteria, have garnered attention for their diverse health benefits, particularly their antimicrobial properties. This study evaluates the antibacterial efficacy of lactic acid bacteria (LAB), selecting Lactobacillus acidophilus postbiotics as the most effective against various pathogenic microorganisms, and focusing on their potential use in topical formulations. In vitro assays were conducted to assess their antimicrobial activity, including minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), well diffusion assay, antibiofilm activity, preservative effectiveness testing, and time-kill assay. The L. acidophilus postbiotic, was identified and quantified by a validated HPLC method, effectively inhibited the growth of Escherichia coli, Staphylococcus aureus, Candida albicans, Pseudomonas aeruginosa, and Aspergillus niger. Furthermore, the formulation containing postbiotics exhibited self-preservative properties. The study also highlights distinct antibacterial effects against Corynebacterium acnes in supernatant, lyophilized, and spray-dried models, with the lyophilized form exhibiting the greatest antimicrobial activity. Based on these results, L. acidophilus postbiotics are a promising candidate for topical applications. They may serve as supportive or complementary components to existing antibiotics and preservative systems, pending further validation.

Protein and peptide drugs have become essential in treating numerous diseases due to their high specificity and therapeutic potential. However, their clinical application faces several challenges, including chemical instability, physical instability, short in vivo half-life, low oral bioavailability, and immunogenicity. These issues reduce drug efficacy and limit patient compliance. This review critically examines these limitations and presents current strategies to address them. PEGylation, the covalent or noncovalent attachment of polyethylene glycol (PEG) molecules to proteins, is highlighted for its ability to increase stability, reduce renal clearance, lower immunogenicity, and extend half-life. The review distinguishes between random and site-specific PEGylation, highlighting site-specific methods that preserve protein activity while optimizing pharmacokinetics. Additionally, the encapsulation of proteins in polymeric and lipid-based delivery systems is discussed to protect drugs from enzymatic degradation, control their release, and enhance absorption. Biobetter approaches, including site-directed mutagenesis, are also presented to improve protein stability and reduce immunogenicity. Market data and approved drug examples illustrate the impact of these strategies. Overall, the article provides a comprehensive overview of innovative pharmaceutical and biotechnological methods that enhance the clinical performance and market viability of protein therapeutics.

Objective: To prepare, characterize, and clinically evaluate postbiotic creams containing Lactobacillus ferment lysate in pediatric patients with Atopic dermatitis (AD). Methods: After preparing different formulations, the formulations were evaluated for stability and physicochemical properties for semisolids, such as physical properties, viscosity, temperature cycle, and pH. Finally, a formulation that showed better physical properties was chosen for further investigation. A randomized clinical trial study was performed with AD referred to the outpatient allergy clinic. The primary outcomes were assessed with the SCORAD index and changes in the proportion of children with clinical improvement/no improvement, deterioration, and recurrence rate. Results: A total of 52 patients (27 vs 25 participants in intervention and placebo groups) were recruited in the study. The pH of creams was 6.00 ± 0.02, which is safe for human skin. In addition, the centrifugation test showed that this formulation was completely homogeneous after centrifugation. The temperature cycle test indicated no change in the structure of the cream. After a two-month follow-up, the mean SCORAD score was 50± 14.5 at baseline and 27.8±10 at the final visit in the postbiotic group. It was also 43± 12 at baseline and 28.2±6 at the final visit in the placebo group. After four months, eleven patients had a recurrence in lesions: 2 (6.9%) in the postbiotic group, versus 9 (30%) in the placebo group. Conclusions: This study demonstrated that postbiotic formulation is cutaneously acceptable and showed a clinically significant improvement, especially in long-term follow-up.

Purpose of Review Global health concerns persist in the realm of cardiovascular diseases (CVDs), necessitating innovative strategies for both prevention and treatment. This narrative review aims to explore the potential of short-chain fatty acids (SCFAs)—namely, acetate, propionate, and butyrate—as agents in the realm of postbiotics for the management of CVDs. Recent Findings We commence our discussion by elucidating the concept of postbiotics and their pivotal significance in mitigating various aspects of cardiovascular diseases. This review centers on a comprehensive examination of diverse SCFAs and their associated receptors, notably GPR41, GPR43, and GPR109a. In addition, we delve into the intricate cellular and pharmacological mechanisms through which these receptors operate, providing insights into their specific roles in managing cardiovascular conditions such as hypertension, atherosclerosis, heart failure, and stroke. Summary The integration of current information in our analysis highlights the potential of both SCFAs and their receptors as a promising path for innovative therapeutic approaches in the field of cardiovascular health. The idea of postbiotics arises as an optimistic and inventive method, presenting new opportunities for preventing and treating cardiovascular diseases.

Objective(s): Today, the non-covalent PEGylation methods of protein pharmaceuticals attract more attention and possess several advantages over the covalent approach. In the present study, Amino Acid-mPEGs (aa-mPEGs) were synthesized, and the human Growth Hormone (hGH) stability profile was assessed in their presence and absence. Materials and Methods: aa-mPEGs were synthesized with different amino acids (Trp, Glu, Arg, Cys, and Leu) and molecular weights of polymers (2 and 5 KDa). The aa-mPEGs were analyzed with different methods. The physical and structural stabilities of hGH were analyzed by SEC and CD spectroscopy methods. Physical stability was assayed at different temperatures within certain intervals. Molecular dynamics (MD) simulation was used to realize the possible mode of interaction between protein and aa-mPEGs. The cell-based method was used to evaluate the cytotoxicity. Results: HNMR and FTIR spectroscopy indicated that aa-mPEGs were successfully synthesized. hGH as a control group is known to be stable at 4 degrees C; a pronounced change in monomer degradation is observed when stored at 25 degrees C and 37 degrees C. hGH:Glu-mPEG 2 kDa with a molar ratio of 1:1 to the protein solution can significantly increase the physical stability. The CD spectroscopy method showed that the secondary structure of the protein was preserved during storage. aa-mPEGs did not show any cytotoxicity activities. The results of MD simulations were in line with experimental results. Conclusion: This paper showed that aa-mPEGs are potent excipients in decreasing the aggregation of hGH. Glu-mPEG exhibited the best-stabilizing properties in a harsh environment among other aa-mPEGs.

The extensive usage of antibiotics and the rapid emergence of antimicrobial-resistant microbes (AMR) are becoming important global public health issues. Many solutions to these problems have been proposed, including developing alternative compounds with antimicrobial activities, managing existing antimicrobials, and rapidly detecting AMR pathogens. Among all of them, employing alternative compounds such as phytochemicals alone or in combination with other antibacterial agents appears to be both an effective and safe strategy for battling against these pathogens. The present review summarizes the scientific evidence on the biochemical, pharmacological, and clinical aspects of phytochemicals used to treat microbial pathogenesis. A wide range of commercial products are currently available on the market. Their well-documented clinical efficacy suggests that phytomedicines are valuable sources of new types of antimicrobial agents for future use. Innovative approaches and methodologies for identifying plant-derived products effective against AMR are also proposed in this review.

Abstract: Background: Acinetobacter is one of the most important pathogens that causes high prevalence of infection in clinical centers. Natural products are major sources of new anti-infective agents and considered as an alternative medicine for the treatment of infectious diseases. Objective: This study aims to evaluate the antibacterial activity of aqueous and methanol extract of Artemisia annua on the clinically isolated Acinetobacter and the combination of the plant extract with amikacin and imipenem. Methods: The aqueous and methanol extract of the aerial parts of this plant was prepared by maceration. Antibacterial activity was determined by the Broth microdilution method. The presence of adeI and adeB genes in Acinetobacter isolates was investigated. The combination effects of antibiotics were performed using the checkerboard method. The effect of plant extract on bacterial efflux pumps was also investigated. Results: MIC values of the methanol extract of A. annua were from 4.46 mg/ml to 8.92 mg/ml. The effects of the interaction of the plant extract with the amikacin and imipenem represent a significant synergistic influence. Findings indicated that the plant extract was able to inhibit the efflux pump remarkably. Conclusion: The combination of the plant extract with amikacin and imipenem can be used in the treatment of infections caused by antibiotic-resistant Acinetobacter and probably other infectious diseases.

Background: Urinary tract infection (UTI) is a common occurrence in females, during pregnancy, and in peri- and postmenopausal women. UTIs are associated with significant morbidity and mortality, and they affect the quality of life of the affected patients. Antibiotic therapy is an effective approach and reduces the duration of symptoms. Development of resistance, adverse effects of antibiotics, and other associated problems lead to establishing the research framework to find out the alternative approaches in controlling UTIs. Natural approaches have been extensively used for the management of various diseases to improve symptoms and also improve general health. Main body: Different databases were employed to identify studies reporting on natural options including herbal medicines, vitamins, trace elementals, sugars, and probiotics without time limitations. Conclusion: Herbal medicines can be effective at the first sign of the infection and also for short-term prophylaxis. Using vitamins, trace elementals, and/or sugars is an effective approach in preventing UTIs, and a combination of them with other antibacterial agents shows positive results. Probiotics have great potential for the threat of antibiotic over-usage and the prevalence of antibiotic-resistant microorganisms. This study may be of use in developing the efficient formulation of treatment of UTI.