The Therapeutic Potential of the Anticancer Activity of Fucoidan: Current Advances and Hurdles.

Several types of cancers share cellular and molecular behaviors. Although many chemotherapy drugs have been designed to weaken the defenses of cancer cells, these drugs may also have cytotoxic effects on healthy tissues. Fucoidan, a sulfated fucose-based polysaccharide from brown algae, has gained much attention as an antitumor drug owing to its anticancer effects against multiple cancer types. Among the anticancer mechanisms of fucoidan are cell cycle arrest, apoptosis evocation, and stimulation of cytotoxic natural killer cells and macrophages. Fucoidan also protects against toxicity associated with chemotherapeutic drugs and radiation-induced damage. The synergistic effect of fucoidan with existing anticancer drugs has prompted researchers to explore its therapeutic potential. This review compiles the mechanisms through which fucoidan slows tumor growth, kills cancer cells, and interacts with cancer chemotherapy drugs. The obstacles involved in developing fucoidan as an anticancer agent are also discussed in this review.

A constitutive unregulated expression of ß-galactosidase in Lactobacillus fermentum M1.

A constitutively ß-galactosidase (LacL)-producing Lactobacillus fermentum M1 isolated from fermented milk was found to produce ß-galactosidase in the presence of glucose. ß-galactosidase activity produced in glucose (30 mM) medium was 2.17 U/mL as compared to 2.27 and 2.19 U/mL with galactose and lactose, respectively. When a combination of glucose (30 or 60 mM) with galactose (30 mM) was used as carbon source, ß-galactosidase activity was not repressed rather was found increased when compared to carbon sources used individually. In real-time PCR analysis of mRNA synthesized on individual and combined carbon sources, repression of the lacL gene expression was not observed. This observation suggests that the strain M1 lacked normal carbon catabolite repression. Examination of nucleotide sequence of lacL identified two catabolite responsive elements (cre): cre1 located downstream near the promoter region and cre2 within the coding sequence. Each of which differed from the 14-bp consensus by a single nucleotide. In cre1, it is C in place of highly conserved T at position 1 in the consensus. In cre 2, it is G in place of C, a residue completely conserved at position 13. Since catabolite genes in Gram-positive bacteria are regulated by carbon catabolite protein A (CcpA) through interaction with DNA at a specific cis-acting cre, it is assumed that base changes at conserved position in the cre elements disrupt CcpA binding and thereby leading to constitutive expression of lacL gene. The study noted to be the first report about the constitutive production of ß-galactosidase in L. fermentum.

Cloning, overexpression, and characterization of a novel alkali-thermostable xylanase from Geobacillus sp. WBI.

An endo-ß-1,4-xylanase gene xynA of a thermophilic Geobacillus sp. WBI from "hot" compost was isolated by PCR amplification. The gene encoding 407 residues were overexpressed in E. coli and purified by Ni-NTA chromatography. The purified enzyme (47 kDa) had a broad pH optimum of 6.0 to 9.0, and was active between 50 and 90 °C. The enzyme retained 100% of its activity when incubated at 65 °C for 1 h under alkaline condition (pH 10.0) and retained 75% activity at pH 11.0. The K(m) and V(max) of the enzyme were 0.9 mg ml(-1) and 0.8 µmol ml(-1) min(-1), respectively. In molecular dynamics simulation at 338 K (65 °C), the enzyme was found to be stable. At an elevated temperature (450 K) specific α-helix and ß-turns of the proteins were most denatured. The denaturation was less in WBI compared with its highest homolog G. stearothermophilus T-6 xylanase with difference of six residues. The results predict that these regions are responsible for the improved thermostability observed over related enzymes. The present work encourages further experimental demonstration to understand how these regions contribute thermostability to WBI xylanase. The study noted that WBI produces a xylanase with unique characteristics, specifically alkali-thermostability.

Draft genome sequence of probiotic bacterium Lactobacillus fermentum S2, isolated from raw cow milk.

Lactobacillus fermentum remains as potential probiotic bacterium that enhances immunological response, produces antimicrobials, acts as food preservative, and lowers blood cholesterol level. We report the draft genome of Lactobacillus fermentum S2 consisting of 1.97 Mb genome size, 52.27% G + C content, 3 rRNA genes, 51 tRNA genes, and 2,004 protein-coding sequences.

Small Molecule Targeting Immune Cells: A Novel Approach for Cancer Treatment.

Conventional and cancer immunotherapies encompass diverse strategies to address various cancer types and stages. However, combining these approaches often encounters limitations such as non-specific targeting, resistance development, and high toxicity, leading to suboptimal outcomes in many cancers. The tumor microenvironment (TME) is orchestrated by intricate interactions between immune and non-immune cells dictating tumor progression. An innovative avenue in cancer therapy involves leveraging small molecules to influence a spectrum of resistant cell populations within the TME. Recent discoveries have unveiled a phenotypically diverse cohort of innate-like T (ILT) cells and tumor hybrid cells (HCs) exhibiting novel characteristics, including augmented proliferation, migration, resistance to exhaustion, evasion of immunosurveillance, reduced apoptosis, drug resistance, and heightened metastasis frequency. Leveraging small-molecule immunomodulators to target these immune players presents an exciting frontier in developing novel tumor immunotherapies. Moreover, combining small molecule modulators with immunotherapy can synergistically enhance the inhibitory impact on tumor progression by empowering the immune system to meticulously fine-tune responses within the TME, bolstering its capacity to recognize and eliminate cancer cells. This review outlines strategies involving small molecules that modify immune cells within the TME, potentially revolutionizing therapeutic interventions and enhancing the anti-tumor response.

Dietary Nutrients and Prevention of Alzheimer's Disease.

Alzheimer's disease is an irrevocable, progressive brain disorder that gradually destroys memory and cognitive skills. One of the extensively studied methods of preventing Alzheimer's disease (AD) progression is by providing a nutritional diet. Several reports have shown that intake of nutritional elements as huperzine A, ursolic acid, vitamins etc., can directly influence pathogenesis of AD. Surprisingly, the occurrence of metabolic disorders due to an unhealthy diet has been known to be a major environmental cause of AD. It has been noted that AD severity can be controlled by supplementing dietary supplements containing huge amounts of health-promoting ingredients. These elements promote cell health, regeneration, and the anti-aging process that specifically interrupt the pathogenic pathways in AD development. Fortunately, incorporating changes in the nutritional content is inexpensive, easy, acceptable, safe, effective, and in most cases, free from major adverse events. Many nutritional phytoconstituents such as flavonoids, alkaloids, and terpenoids are still being evaluated in the hope of identifying a successful therapy for AD. This review discusses the therapeutical potential of several key nutrients that have been researched for treating AD treatment and the method of their neuroprotective intervention.

Exploring the Role of Stem Cell Therapy in Treating Neurodegenerative Diseases: Challenges and Current Perspectives.

Several human neurological disorders, such as Parkinson's disease, Alzheimer's disease, amyotrophic lateral sclerosis, Huntington's disease, spinal cord injury, multiple sclerosis, and brain stroke, are caused by the injury to neurons or glial cells. The recent years have witnessed the successful generation of neurons and glia cells driving efforts to develop stem-cell-based therapies for patients to combat a broad spectrum of human neurological diseases. The inadequacy of suitable cell types for cell replacement therapy in patients suffering from neurological disorders has hampered the development of this promising therapeutic approach. Attempts are thus being made to reconstruct viable neurons and glial cells from different stem cells, such as embryonic stem cells, mesenchymal stem cells, and neural stem cells. Dedicated research to cultivate stem cell-based brain transplantation therapies has been carried out. We aim at compiling the breakthroughs in the field of stem cell-based therapy for the treatment of neurodegenerative maladies, emphasizing the shortcomings faced, victories achieved, and the future prospects of the therapy in clinical settings.

Plasmid-Based Gene Expression Systems for Lactic Acid Bacteria: A Review.

Lactic acid bacteria (LAB) play a very vital role in food production, preservation, and as probiotic agents. Some of these species can colonize and survive longer in the gastrointestinal tract (GIT), where their presence is crucially helpful to promote human health. LAB has also been used as a safe and efficient incubator to produce proteins of interest. With the advent of genetic engineering, recombinant LAB have been effectively employed as vectors for delivering therapeutic molecules to mucosal tissues of the oral, nasal, and vaginal tracks and for shuttling therapeutics for diabetes, cancer, viral infections, and several gastrointestinal infections. The most important tool needed to develop genetically engineered LABs to produce proteins of interest is a plasmid-based gene expression system. To date, a handful of constitutive and inducible vectors for LAB have been developed, but their limited availability, host specificity, instability, and low carrying capacity have narrowed their spectrum of applications. The current review discusses the plasmid-based vectors that have been developed so far for LAB; their functionality, potency, and constraints; and further highlights the need for a new, more stable, and effective gene expression platform for LAB.

Lactococcus lactis Delivery of Surface Layer Protein A Protects Mice from Colitis by Re-Setting Host Immune Repertoire.

Inflammatory bowel disease (IBD) is characterized by gastrointestinal inflammation comprised of Crohn's disease and ulcerative colitis. Centers for Disease Control and Prevention report that 1.3% of the population of the United States (approximately 3 million people) were affected by the disease in 2015, and the number keeps increasing over time. IBD has a multifactorial etiology, from genetic to environmental factors. Most of the IBD treatments revolve around disease management, by reducing the inflammatory signals. We previously identified the surface layer protein A (SlpA) of Lactobacillus acidophilus that possesses anti-inflammatory properties to mitigate murine colitis. Herein, we expressed SlpA in a clinically relevant, food-grade Lactococcus lactis to further investigate and characterize the protective mechanisms of the actions of SlpA. Oral administration of SlpA-expressing L. lactis (R110) mitigated the symptoms of murine colitis. Oral delivery of R110 resulted in a higher expression of IL-27 by myeloid cells, with a synchronous increase in IL-10 and cMAF in T cells. Consistent with murine studies, human dendritic cells exposed to R110 showed exquisite differential gene regulation, including IL-27 transcription, suggesting a shared mechanism between the two species, hence positioning R110 as potentially effective at treating colitis in humans.

Contraceptive efficacy of recombinant fusion protein comprising zona pellucida glycoprotein-3 fragment and gonadotropin releasing hormone.

Contraceptive vaccines have been used for the management of wildlife population. In the present study, we have examined the contraceptive potential of Escherichia coli-expressed recombinant fusion protein comprising of 'promiscuous' T cell epitope of tetanus toxoid [TT; amino acid (aa) residues 830-844] followed by dilysine linker (KK), dog ZP3 fragment (aa residues 307-346), triglycine spacer (GGG), T cell epitope of bovine RNase (bRNase; aa residues 94-104), GnRH, T cell epitope of circumsporozoite protein of Plasmodium falciparum (CSP; aa residues 362-383), and GnRH. SDS-PAGE analysis of the purified refolded protein revealed a dominant ∼12 kDa band, which in Western blot reacted with mouse polyclonal antibodies against dog ZP3 fragment and mouse monoclonal antibodies against GnRH. Immunization of female FvB/J mice following two booster schedule with the above recombinant protein supplemented with alum led to high antibody titres against the immunogen as well as ZP3 and GnRH as determined by ELISA. The immune sera reacted with zona pellucida of mouse oocyte and also inhibited in-vitro fertilization. The qRT-PCR studies showed decrease in the ovarian GnRH receptor in mice immunized with the recombinant fusion protein. Mating studies revealed high contraceptive efficacy of the recombinant protein as in two independent experiments, 90% of the immunized female mice failed to conceive. Following one booster immunization schedule, 50% of the immunized female mice failed to conceive. However, in adjuvanted controls, all the female mice became pregnant. To conclude, the recombinant protein described herein has a good potential to be developed as candidate contraceptive vaccine.

Ovarian and oocyte targets for development of female contraceptives.

INTRODUCTION: Steroid hormone-based contraceptives have been used by women for long time since their introduction. Efforts have been made to make steroidal contraceptives cost-effective, safe and improve their users' compliance. In addition, attempts have been made to develop nonsteroidal contraceptives. Contraceptive vaccines have been investigated as an alternate strategy for contraception. AREAS COVERED: The currently used steroidal contraceptives are reviewed. In addition, status of emerging nonsteroidal contraceptives that inhibit folliculogenesis, oocyte maturation, ovulation and endometrium receptivity targeting phosphodiesterase 3, angiopoietins, gonadotropin-releasing hormone, COX-2, progesterone/estrogen receptor and follicle-stimulating hormone receptor are presented. Various approaches to develop contraceptive vaccines aiming to inhibit ovarian follicle development, ovulation, fertilization and implantation including their current applications and limitations are discussed. EXPERT OPINION: Development of new nonsteroidal contraceptives, in addition to long-acting steroidal contraceptives, is pertinent for offering wider choice to women. It is imperative that basic research to discover new targets in the ovaries must be undertaken to facilitate development of novel contraceptives. Further, efforts on studying the feasibility and safety of contraceptive vaccines may be continued to bring these within the realm of application as contraceptives for humans.