Abstract

Curcumin is among the most well-studied natural substances, known for its biological actions within the central nervous system, its antioxidant and anti-inflammatory properties, and human health benefits. However, challenges persist in effectively utilising curcumin, addressing its metabolism and passage through the blood-brain barrier (BBB) in therapies targeting cerebrovascular diseases. Current challenges in curcumin's applications revolve around its effects within neoplastic tissues alongside the development of intelligent formulations to enhance its bioavailability. Formulations have been discovered including curcumin's complexes with brain-derived phospholipids and proteins, or its liposomal encapsulation. These novel strategies aim to improve curcumin's bioavailability and stability, and its capability to cross the BBB, thereby potentially enhancing its efficacy in treating cerebrovascular diseases. In summary, this review provides a comprehensive overview of molecular pathways involved in interactions of curcumin and its metabolites, and brain vascular homeostasis. This review explores cellular and molecular current aspects, of curcumin-based effects with an emphasis on curcumin's metabolism and its impact on pathological conditions, such as neurodegenerative diseases, schizophrenia, and cerebral angiopathy. It also highlights the limitations posed by curcumin's poor bioavailability and discusses ongoing efforts to surpass these impediments to harness the full therapeutic potential of curcumin in neurological disorders.

Abstract

Abstract

Alzheimer's disease (AD) is known as the primary and most common cause of dementia in the middle-aged and elderly population worldwide. Chemical analyses of B. pendula leaf extract (BPE), performed using spectrophotometric and chromatographic methods (LC/MS), revealed high amounts of polyphenol carboxylic acids (gallic, chlorogenic, caffeic, trans-p-coumaric, ferulic, and salicylic acids), as well as flavonoids (apigenin, luteolin, luteolin-7-O-glucoside, naringenin, hyperoside, quercetin, and quercitrin). Four groups of Wistar rats were used in this experiment (n = 7/group): control (untreated), A beta(1-42) (2 mu g/rat intracerebroventricular (i.c.v.), A beta(1-42) + BPE (200 mg/Kg b.w.), and DMSO (10 mu L/rat). On the first day, one dose of A beta(1-42) was intracerebroventricularly administered to animals in groups 2 and 3. Subsequently, BPE was orally administered for the next 15 days to group 3. On the 16th day, behavioral tests were performed. Biomarkers of brain oxidative stress Malondialdehyde (MDA), (Peroxidase (PRx), Catalase (CAT), and Superoxid dismutase (SOD) and inflammation (cytokines: tumor necrosis factor -alpha (TNF-alpha), Interleukin 1 beta (IL-1 beta), and cyclooxygenase-2 (COX 2)) in plasma and hippocampus homogenates were assessed. Various protein expressions (Phospho-Tau (Ser404) (pTau Ser 404), Phospho-Tau (Ser396) (pTau Ser 396), synaptophysin, and the Nuclear factor kappa B (NFkB) signaling pathway) were analyzed using Western blot and immunohistochemistry in the hippocampus. The results show that BPE diminished lipid peroxidation and neuroinflammation, modulated specific protein expression, enhanced the antioxidant capacity, and improved spontaneous alternation behavior, suggesting that it has beneficial effects in AD.

Abstract

Alkylating agents such as cyclophosphamide (CPA) are commonly used in cytotoxic or immunosuppressive therapies for different types of diseases. One of the main secondary effects of such therapy is the reduction in follicular reserve, targeting the primordial follicles. The aim of this study was to investigate the antioxidant and protective effects of Plantago sempervirens extract on the follicular pool. The experiment was performed on Wistar female rats, for 21 days. They were divided into five groups according to the treatment they received (Control, CPA (200 mg/kg BW), P. sempervirens extract in three different doses-25/50/100 dw/mL ethanol extract (5 mL/kg BW)). The investigations regarded enzymatic and non-enzymatic nitro-oxidative stress, hormone levels (FSH and estrogen), TEM sections of the ovaries, and oestrus cycle monitorization. CPA strongly increased the oxidative stress (TOS-32.8 mmol H2O2/L; NO-68.60 mu mol/L; OSI-6.82), alongside a depletion of FSH and a blockage of the oestrus cycle in the metestrus phase. The follicular pool was strongly depleted during CPA exposure, but FSH concentration and the TEM images of the cells revealed a significant improvement after treatment, as the dose increases (P3). Therefore, these findings reveal that P. sempervirens therapy could have a potential protective effect against CPA-induced acute damages in the ovaries, as well as maintaining a functional oestrus cycle.

Abstract

Hemoglobin-based oxygen carriers (HBOCs) have been proposed and tested for several decades for the treatment of hemorrhage. We have previously proposed replacing hemoglobin (Hb) in HBOC with the oxygen-carrying protein hemerythrin (Hr), from marine worms, showing that Hr-based derivatives can perform at least as well or even better than Hb-based HBOC in a range of in vitro assays involving oxidative and nitrosative stress as well as in top-up animal models, where small amounts of Hr- or Hb-HBOC were injected into rats. Here, these experiments are extended to a hemorrhage experiment, in which Hr polymerized with glutaraldehyde, alone or conjugated with human serum albumin, is administered after a loss of 20-30% blood volume. The performance of these preparations is compared with that of Hb-based HBOC measured under the same conditions. Polymerized Hr is found to decrease the survival rate and can hence cannot be used as an oxygen carrier in transfusions. On the other hand, an Hr-albumin copolymer restores survival rates to 100% and generally yields biochemical and histological parameters similar to those of glutaraldehyde-polymerized bovine hemoglobin, with the exception of an acid-base imbalance. The latter may be solved by employing an allogeneic albumin as opposed to the human albumin employed in the present study.

Abstract

Curcumin (CCM) is one of the most frequently explored plant compounds with various biological actions such as antibacterial, antiviral, antifungal, antineoplastic, and antioxidant/anti-inflammatory properties. The laboratory data and clinical trials have demonstrated that the bioavailability and bioactivity of curcumin are influenced by the feature of the curcumin molecular complex types. Curcumin has a high capacity to form molecular complexes with proteins (such as whey proteins, bovine serum albumin, beta-lactoglobulin), carbohydrates, lipids, and natural compounds (e.g., resveratrol, piperine, quercetin). These complexes increase the bioactivity and bioavailability of curcumin. The current review provides these derivatization strategies for curcumin in terms of biological and physico-chemical aspects with a strong focus on different type of proteins, characterization methods, and thermodynamic features of protein-curcumin complexes, and with the aim of evaluating the best performances. The current literature review offers, taking into consideration various biological effects of the CCM, a whole approach for CCM-biomolecules interactions such as CCM-proteins, CCM-nanomaterials, and CCM-natural compounds regarding molecular strategies to improve the bioactivity as well as the bioavailability of curcumin in biological systems.

Abstract

The present work shows the biochemical and structural fundamentals for the stress induced anxiety and stress adjustment response of the CA3 hippocampus area. Adult male Wistar rats were repeatedly exposed to a 3 h day restraint stress, for either 3 or 6 days. The concentration of corticosterone and testosterone in the CA3 hippocampus area was divergent, while oxidative stress was progressively increased during the stress exposure. The mitochondrial lysis in the CA3 neurons confirmed the oxidative stress events. Immunohistochemical findings showed that oligodendrocytes (OCs) proliferation and neuroglobin (Ngb) expression were stimulated, whereas MeCP2 expression was decreased as a balance reaction in stress exposure under corticosterone signaling. Remarkably, ultrastructural changes such as mitochondrial lysis, endoplasmic reticulum swelling, and perivascular lysis with platelets adherence to endothelium in the CA3 area were seen in the 6th day of restraining. The anxiety-like behavior was noticed 6 days later after stress exposure. These results suggest that the duration of the exposure, but not the intensity of the stress, is the key factor in the stress-buffering function by the CA3 hippocampus area via up-regulation of the Ngb-OCs bionome. The imbalance of the Ngb-OCs communication may be involved in the development of CA3-dependent anxious behavior.

Abstract

Raman microspectroscopy was tested as an alternative/complementary method for biochemical evaluation of the synaptosomes obtained from neonatal rat brain prenatally exposed to sodium valproate and treated with allicin. Spectrophotometric assays of several oxidative stress markers (catalase, superoxide dismutase, total thiols) and acetylcholine esterase activity revealed the redox balancing function and pro-cholinergic effect of the allicin as compared to the valproate effect. Raman evaluation showed no significant changes in our experimental conditions. Different concentrations and volumes of the synaptosomes vesicles must be tested for the optimal Raman examination of these purified synaptosomes.

Abstract

Hemoglobin- (Hb-) based oxygen carriers (HBOC) have for several decades been explored for treatment of hemorrhage. In our previous top-up tests, HBOC with lowerin vitroprooxidant reactivity (incorporating a peroxidase or serum albumin to this end) showed a measurable but small improvement of oxidative stress-related parameters. Here, such HBOCs are tested in a hemorrhage set-up; ovine hemoglobin is also tested for the first time in such a setting, based onin vitrodata showing its improved performance versus bovine Hb against oxidative and nitrosative stress agents. Indeed, ovine Hb performs better than bovine Hb in terms of survival rates, arterial tension, immunology, and histology. On the other hand, unlike in the top-up models, where the nonheme peroxidase rubrerythrin as well as bovine serum albumin copolymerized with Hb were shown to improve the performance of HBOC, in the present hemorrhage models rubrerythrin fails dramatically as HBOC ingredient (with a distinct immunological reaction), whereas serum albumin appears not feasible if its source is a different species (i.e., bovine serum albumin fares distinctly worse than rat serum albumin, in HBOC transfusions in rats). An effect of the matrix in which the HBOCs are dissolved (PBS versus gelofusine versus plasma) is noted.

Abstract

Site-directed spin labeling and EPR characterization (continuous wave as well as DEER) of two blood substitute candidates is described for the first time: glutaraldehyde-polymerized bovine hemoglobin and the related hemoglobin-albumin copolymer. In vitro, with two different types of cell cultures, these spin-labeled candidates are relatively stable; however, they appear to be rapidly reduced in vivo, most likely via removal or reduction of the spin label (as opposed to removal of the blood substitute candidate from the circulatory system altogether).