Current Medicinal Chemistry - Volume 24, Issue 40, 2017

Background: Cerebrovascular and cardiovascular diseases are caused by impairment of the brain and/or heart circulation. Insufficient blood flow results in decreased oxygen delivery (ischemia), which affects mitochondrial functioning and consequently leads to insufficient ATP production. The predominant mitochondrial outer membrane protein, the voltagedependent anion selective channel (VDAC), is considered to be crucial for mitochondrial functioning. In human mitochondria, as in other vertebrates, three isoforms of VDAC (VDAC1-VDAC3) are present, and they likely play different roles. Objective: In this review, we summarize the available data concerning VDAC involvement in cardiovascular and cerebrovascular diseases with regard to VDAC isoforms and discuss the use of possible VDAC-related intervention targets as well as known VDAC-interacting and cytoprotection- conferring molecules in the treatment of cerebrovascular and cardiovascular diseases. Method and Results: The suitable references on disorders defined as cerebrovascular and cardiovascular diseases as well as VDAC contribution to these conditions were searched using PubMed and ClinicalTrials.gov databases. The review is based on the 138 carefully selected articles. Conclusion: Mitochondrial dysfunction triggered by changes in VDAC properties undoubtedly contributes to cell death and related diseases, including cerebrovascular and cardiovascular diseases. Thus, beside diagnostic application, modulation of VDAC activity, including its isoforms, is thus of great importance for the development of efficient therapeutic interventions. Moreover, identification of VDAC-interacting molecules that protect against mitochondrial dysfunction and cell death seems to be of great importance.

Background: The voltage-dependent anion channel 1 (VDAC1), an outer mitochondria membrane protein, functions as a mitochondrial governor, controlling transport of metabolites in and out of the mitochondria and energy production, while also coordinating glycolysis and oxidative phosphorylation. VDAC1 plays a key role in mitochondria-mediated apoptosis by functioning in the release of apoptotic proteins located in the inter-membranal space and due to its association with pro- and anti-apoptotic proteins. Thus, VDAC1 is considered as a promising target for controlling apoptosis. Methods: We reviewed published data presenting accumulated evidence suggesting that VDAC1 oligomerization represents an important step in the intrinsic mitochondria-mediated apoptosis pathway. Results: The published data support the proposal that VDAC1 oligomerization leads to the formation of a large pore that allows the release of pro-apoptotic proteins to the cytosol, thereby, activation of apoptosis. Evidence for the relationship between VDAC1 expression levels and induction of apoptosis are presented. This includes the finding that almost all apoptosis stimuli induce VDAC1 over-expression shifting VDAC1 from a monomeric to an oligomeric assembly, corresponding to the Cyto c release channel. Copounds or conditions inducing VDAC1 over-expression, VDAC1 oligomerization and apoptosis are presented. Likewise, VDAC1-interacting molecules, that inhibit both VDAC1 oligomerization and apoptosis are also presented. Conclusion: This review highlights the findings about VDAC1 oligomerization as a potential target for controlling apoptosis, specifically using drugs to induce apoptotic cell death in cancer and inhibit apoptosis in neurodegenerative diseases, as well as possible VDAC1-based therapeutic applications.

Background: VDAC (Voltage-Dependent Anion selective Channel) is a small family of abundant pore-forming proteins located in the outer mitochondrial membrane. Their role range from the most intuitive, the formation of a hydrophilic conduit through the membrane thanks to its beta-barrel structure, to less understood functions that make them essential actors in the cross-talk between the bioenergetics metabolism and the cytosol components. Due to this localization, VDAC1, in particular, has been reported to be involved in apoptosis, Hexokinase and tubulin binding, and in the Warburg effect. For these reasons, an involvement of VDAC in cancer is considered consequential and a number of compounds have been proposed and used in experimental trials to demonstrate the efficacy of molecules affecting the functions of VDAC. Objectives: In this work, we thus survey the literature describing drug compounds acting on the cancerous proliferation through VDAC. Three main categories have been assigned: molecules acting on the VDAC-Hexokinase binding, molecules directly inhibiting the VDAC conductance, molecules affecting the expression levels of the VDAC gene. The application of biological peptides for this purpose is also considered. Conclusion: Since the knowledges about the functional properties of VDAC protein are still insufficient, VDAC as a pharmacological target in the fight against cancer is still a very open, but very promising, field.

Background: The Voltage Dependent Anion Channel (VDAC) proteins represent the most important pore-forming proteins of the mitochondrial outer membrane, directly involved in metabolism and apoptosis regulation. Literature has highlighted a key role of VDACs in mitochondrial dysfunction typical of many neurodegenerative disorders. In particular, the principal isoform VDAC1 represents the main mitochondrial docking site of many misfolded proteins, such as amyloid β and Tau in Alzheimer's disease, α-synuclein in Parkinson's disease and several SOD1 mutants in Amyotrophic Lateral Sclerosis. The interaction of misfolded proteins with VDAC1 has a strong impact on both cellular bioenergetics and apoptosis' pathways alteration. Therefore, VDACs represent a promising therapeutic target in neurodegeneration. Objective: This review summarizes the roles of VDAC isoforms, and particularly of VDAC1, in the most common neurological disorders and analyzes in detail molecules and peptides available so far, able to interact and modulate VDAC1 in any considered pathological condition. Conclusion: This review offers a description of the most promising therapeutic strategies acting on VDAC1, for the treatment of neurodegenerative diseases.

Background: Anti-apoptotic members of the Bcl-2 family of proteins are upregulated in a majority of cancers and are potential therapeutic targets. Fragment-based design led to the development of clinical candidates that target Bcl-xL/Bcl-2. Although these BclxL/ Bcl-2 inhibitors showed promise in pre-clinical studies, resistance to several Bcl-xL inhibitors was observed, when used alone. This is attributed to the over-expression of Mcl-1, another member of the Bcl-2 family of proteins. Indeed, Mcl-1 is highly amplified in numerous cancers, suggesting that it may contribute to malignant cell growth and evasion of apoptosis. Therefore, significant efforts have been made toward the development of direct Mcl-1 inhibitors for cancer therapy. Methods: Following an extensive search of peer-reviewed articles on the development of Mcl-1-selective inhibitors, the literature retrieved is chronologically arranged and discussed in this review article. Results: We have included 147 articles in this review; including articles that describe the development of stapled peptides with improved binding affinity as Mcl-1-selective BH3 mimetics, those describing fragment-based and structure-based design of small molecule Mcl-1 inhibitors by various research groups, and those detailing the use of natural products and their derivatives as potential Mcl-1 inhibitors. Conclusion: The therapeutic potential of targeting the Mcl-1 protein for cancer drug discovery is vast. Stapling BH3 peptides, as well as the development of small molecule inhibitors as BH3 mimetics, are viable strategies to develop selective Mcl-1 inhibitors. With no clinically approved candidate in hand, additional modes of perturbing the biological function of this protein will aid drug discovery efforts.

Background: In addition to the considerable number of different chlorophyll structures originated naturally, prominent research is made to produce new specific semisynthetic structures. The final target is to obtain chlorophyll derivatives with even better bioactive properties than those of the natural parent compounds. Method: A detailed, extensive and critic literature search has been made in Web of Science™. Results: Great efforts are applying to optimize the function of chlorophyll-based photosensitizers, to understand the molecular mechanisms of the antioxidant and antigenotoxic properties of chlorophyll derivatives and, lastly, to investigate new biological actions of them. However, the fundamental physiological functions of the chlorophylls are their physicochemical properties. Conclusion: This review aims to reflect the chemical grounds of the healthy and/or medical features of chlorophylls, including the consequences, advantages or even new actions that modifications over the chlorophyll structure introduce. Finally, new perspectives in the functionality of chlorophylls at molecular level are discussed.