Design of advanced multifunctional biomaterial-based biomimetic and pH-responsive hybrid nanocarriers for antibiotic delivery against bacterial infections and sepsis = Ukwakhiwa kwama-haybridiangezona izedlulisela asebenza ngezindlela ezahlukahlukene enziwe nge-biomimetic eyakhiwe ngezinto eziphilayo abe ezwana futhi ne-pH. Lawa angezona izedluliseli ahambisa izinqindimagciwane ezilwisana nokutheleleka kwegciwane kanye nokudlanga kwekhovidi-19.

Abstract

Despite the notable improvements in the management of bacterial infections and sepsis, the mounting threat of antibiotic resistance on a global scale is leading towards a post-antibiotic era. Nano-drug delivery systems have improved the delivery and efficacy of various antibiotics. Biomimicry and stimuli-responsiveness have recently been used to improve the targetability of these nanocarriers, and enhance their localization at infected sites, thus improving overall therapeutic outcomes and reducing toxicity. Strategies such as targeting bacterial biofilms and efflux pumps can further enhance the delivery and effectiveness of antibiotics. Developing smart biomaterials with multifunctional properties to confer biomimetic, stimuli-responsive and antivirulence properties to antibiotic nanocarriers is the focus of ongoing research. Therefore, the general aim of this study was to investigate the potential of various novel multifunctional biomaterial-based hybrid nanocarriers (HNs), including biomimetic and/or pH-responsive HNs in enhancing the targeted delivery of antibiotics and modulating the proinflammatory response against bacterial infections and sepsis. In this study, two biomaterials with multifunctional activities, hyaluronic acid-lysine conjugate (HA-Lys) and tannic acid (TA), were employed to design, formulate, and extensively characterize innovative biomimetic and pH-responsive HNs for efficient and targeted delivery of antibiotics. The novel HA-Lys was synthesized and fully characterized using proton nuclear magnetic resonance (1H NMR) spectroscopy and Fourier-transform infrared spectroscopy (FT-IR). Then it was successfully employed with tocopherol succinate (TS) and Oleylamine (OLA) to fabricate biomimetic pH-responsive vancomycin-loaded hybrid nanostructured lipid carriers (VCM-HNLCs). The prepared VCM-HNLCs were spherical and had average diameters, zeta potential, polydispersity index, drug encapsulation efficiency and loading capacity of 110.77  1.69 nm, 0.11  0.02, -2.92  0.21 mV, 76.27  1.20 % and 8.36  0.25 %, respectively. Both HA-Lys conjugate and its respective nanoformulations had excellent biosafety profiles (>70 % cell viability and ˂ 1 % hemolytic effect). Possible VCM-HNLCs competitive inhibition activity to toll-like receptors 2 and 4 (TLR2 and TLR4) was demonstrated via microscale thermophoresis (MST) analysis, which showed a 5-times and 16-times lower Kd values than their natural substrates peptidoglycan (PGN) and lipopolysaccharide (LPS), respectively. VCM-HNLCs exhibited a pH-responsive drug release profile under acidic conditions, higher bacterial killing kinetics, enhanced antibacterial, anti-biofilm, and efflux pump inhibition activities over bare VCM. Also, they showed an improved activity in neutralizing reactive oxygen species (ROS) and modulating the inflammatory response induced by LPS. On the other hand, tannic acid (TA) and Oleylamine (OLA) were successfully employed to formulate biomimetic ciprofloxacin-loaded tannic acid hybrid nanoparticles (CIP-loaded TAH-NPs) to enhance the efficacy of CIP against bacterial infections and sepsis. The prepared HNs had onion-shaped morphology, with average diameters, zeta potential, polydispersity index, drug encapsulation efficiency and loading capacity of 85.65 ± 0.89 nm, 0.126 ± 0.01, +16.3 ± 0.23 mV, 68.73 ± 0.54 % and 6.86 ± 0.09 %, respectively. The hemolysis and MTT assays confirmed the biosafety and non-hemolytic activity of CIP-loaded TAH-NPs formulations (>70 % cell viability and ˂ 1 % hemolytic effect). The results of MST investigations and in-silico simulations demonstrated that TA and its nanoformulation (CIP-loaded TAH-NPs) competitively inhibited TLR4 compared to its natural substrate LPS. CIP-loaded TAH-NPs showed a diffusion-based sustained release profile at physiological pH 7.4. Also, in comparison to bare CIP, the hybrid nanovesicles demonstrated improved antibacterial, anti-biofilm and efflux pump inhibition properties, as well as faster bacterial killing kinetics. Moreover, they showed a significant neutralization of ROS and the ability to control the inflammatory responses brought on by LPS. In summary, VCM-HNLCs and CIP-loaded TAH-NPs were successfully formulated and showed significant improvement in antibiotics efficacy and overall therapeutic outcomes. This study confirmed the potential of biomimetic stimuli-responsive antibiotic hybrid nanocarriers for enhancing antibiotic efficacy against bacterial sepsis and addressing the antimicrobial resistance crisis. The data from this study has resulted in one first-authored review article, two first-authored research publications and one co-authored review article.

Iqoqa.

Nakuba kubonakala ukuba ngcono ukwelashwa kokutheleleka ngamagciwane kanye nokudlanga kwekhovidi-19 ukuqina kokuphikisana nokusebenza kwezinqandimagciwane emhlabeni jikelele kuholela ekuthi kubhekwe esikhathini lapho kuzobe kungasasetshenziswa izinqandimagciwane. Izindlela zokuhanjiswa kwemithi eyizinhlayiya ezincane kakhulu ezaziwa ngama-nano-drug zenze kusheshe ukuhanjiswa kanye nokusebenza ngendlela efanele kwezinqandimagciwane ezihlukahlukene. Sekusetshenziswe indlela yokubukela emvelweni kanye nokubheka ukusebenza kwezikhuthazi ukuze kuthuthukiswe ukufinyelela lapho kufanele khona kwalawa ma-nano-carrier, futhi kuthuthukiswe nokuzinza kwawo ezingxenyeni zomzimba ezitheleleke ngegciwane okwenza kusheshe kubonakale ukuphola ngokushesha kunciphe noshevu emithini. Amasu afana nokuhlasela ungwengwezi olwemboze amagciwane kanye namaphrotheyni akhipha ubuthi kumaseli aziwa ngama-efflux pump angaphinde athuthukise ukuhanjiswa kanye nokusebenza kahle kwezinqandimagciwane. Ucwaningo oluqhubekayo lusekuthuthukiseni izinto zokusebenza ezakhiwe ngemvelo zibe zinezimo ezisebenza ngokuhlukahlukana ukuze zinikeze amandla okumelana nezikhuthazi kanye nokulwisana namagciwane kuma-nanocarrier. Ngakho-ke, inhloso yalolu cwaningo ukuhlola ukuthi ama-nanocarrier ayizinhlobo ezintsha ezisebenza ngezindlela ezihlukahlukene abe eyingxubevange enziwe ngokususelwe emvelweni (HNs) okuhlanganiswa kuwo ama-HNs akopela ekusebenzeni kwemvelo kanye/noma asebenzisana ne-pH angasebenza kangakanani noma kanjani ukuthwala izinqandimagciwane ziye ngqo lapho okumele ziye khona kanye nokulawula ukungavuvukali uma kunokutheleleka ngegciwane noma kune-sepsisi. Kulolu cwaningo kwasetshenziswa izinto zokusebenza ezakhiwe ngemvelo ezimbili ezenza imisebenzi ehlukahlukene i-hyaluronic acid-lysine conjugate (HA-Lys) kanye ne-tannic acid (TA) ukuze kwakhiwe futhi kucatshangwe kabanzi ama-HNs aphambili ngokubukela emvelweni futhi asebenzisanayo ne-pH ukuze kuthwaleke izinqandimagciwane ngendlela efanele nezifika kahle lapho kumele ziyosebenza khona. Kwahlanganiswa i-HA-Lys entsha yahlolisiswa kusetshenziswa i-spectroscopy esiyi- proton nuclear magnetic resonance (1H NMR) kanye ne- Fourier-transform infrared spectroscopy (FT-IR). Yase isetshenziswa ngempumelelo isetshenziswa ne- tocopherol succinate (TS) kanye ne- Oleylamine (OLA) ekwenzeni izithuthi ezisamafutha ezisebenza njengokwasemvelweni futhi okusebenzisanayo ne-pH kube kuyingxubevange egcwele i-vancomycin (VCM-HNLC). Ama-VCM-HNLC akhiwa ayeyimbulunga enobubanzisiyingi obuyisilinganisomaphakathi, i-zeta potential, i-polydispersity index, ukugcineka ngokufanele kobungako bomuthi ozinze lapho okumele uhlasele khona , okwaziwa nge- drug encapsulation efficiency, kanye nobungako bomuthi ongafakwa oyi- 110.77  1.69 nm, 0.11  0.02, -2.92  0.21 mV, 76.27  1.20 % and 8.36  0.25 %, ngokulandelana. Kokubili ukuhlangana kwesikhashana kwe-HA-Lys kanye nama-nanoformulation ayo alandelayo kwakhombisa isimo esihle sokuphepha (>70 % ukusebenza kwamaseli kanye nemithelela kulokho okuhlangene nokuqhuma kwemithambo yegazi ˂ 1 %). Kwavela ukuthi kungenzeka kube nokuncintisana nezithiyo ze-VCM-HNLC kuma-receptor 2 kanye no-4(TLR2 kanye ne-TLR4) asebenza njengabalindisango. Lokhu kwakhonjiswa uhlaziyo lwe-microscale thermophoresis (MST) olwakhombisa ukwehla kwama-K value ngokuphindwe ka-5 kanye naka-16 uma kuqhathaniswa nama- natural substrates peptidoglycan (PGN) kanye nama- lipopolysaccharide (LPS)awo, ngokulandelana. Ama-VCM-HNLC akhombisa ukukwazi ukukhipha umuthi osebenzisana ne-pH ngaphansi kwezimo ezine-esidi, uhlololumbanozithako oluphezulu ekubulaleni amagciwane, amandla aphezulu okulwisana namgciwane, ukulwisana nongwengwezi lokuphilayo, kanye nokusebenza kwezithibi ze-efflux pump kuma-VCM ahlezi obala. Okunye futhi, akhombisa ukusebenza kangcono ekudambiseni ama-reactive oxygen species (ROS) kanye nasekwenyuseni izinga lokulwa nokuvuvukala okudalwa yi-LPS. Ngakolunye uhlangothi, kwasetshenziswa ngempumelelo i-tannic acid (TA) kanye ne-Oleylamine (OLA) ukwakha ama- ciprofloxacin-loaded tannic acid hybrid nanoparticle (CIP-loaded TAH-NP) akhiwe njengokwemvelo ukwenyusa izinga lokusebenza ngendlela efanele kwama-CIP ekulwisaneni nokutheleleka ngegciwane kanye ne-sepsisi. Ama-HN alungiselelwe ayenesimo esifana no-anyanisi enobubanzisiyingi obuyisilinganisomaphakathi, i-zeta potential, i-polydispersity index, ukugcineka ngokufanele kobungako bomuthi ozinze lapho okumele uhlasele khona , okwaziwa nge- drug encapsulation efficiency, kanye nobungako bomuthi ongafakwa oyi-85.65 ± 0.89 nm, 0.126 ± 0.01, +16.3 ± 0.23 mV, 68.73 ± 0.54 % and 6.86 ± 0.09 %, ngokulandelana. Ama-aseyi aqondene nokuqhuma kwemithambo yegazi kanye ne-MTT akuqinisekisa ukuphepha emzimbeni kanye nokusebenza kwama-TAH-NP afakwe i-CIP angayiqhumisi imithambo yegazi ((>70 % ukusebenza kwamaseli kanye nemithelela kulokho okuhlangene nokuqhuma kwemithambo yegazi ˂ 1 %). Imiphumela yokuhlola kwe-MST kanye nokulingiswa okwenziwa yikhompyutha yaveza ukuthi i-TA kanye nokwakheka kwayo (CIP-loaded TAH-NP) kwakhombisa ukuthiba i-TLR4 ngempumelelo uma kuqhathaniswa neLPS ewuhlobo lwemvelo. Ama-TAH-NP afakwe i-CIP akhombisa ukuthi ayakwazi ukukhipha ngokusabalalisa okunganqamukiyo ezingeni le-pH 7.4. Okunye futhi, uma kuqhathaniswa ne-CIP engamboziwe izikhwanyana ezincane ezaziwa nge-hybrid nanovesicles emzimbeni zakhombisa ukulwisana namagciwane okungcono, kanjalo nasongwengwezini kanye nokuthiba i-efflux pump, kanye nhlololumbanozithako lokubulala amagciwane ngokushesha. Kanti futhi zakhombisa amandla amakhulu okunciphisa i-ROS kanye nokukwazi ukulawula ukuvuvukala okudalwa yi-LPS. Kafushane, ama-VCM-HNLC kanye namaTAH-NP afakwe i-CIP akhiwa ngempumelelo futhi akhombisa ubungcono obukhulu ekusebenzeni kwezinqandimagciwane kanye nemiphumela yokwelapha ngobubanzi. Lolu cwaningo lwaqinisekisa amandla ama-nanocarrier ayi-haybhridi athwala izinqandimagciwane abe ekwazi ukusebenzisana nezikhuthazi ekuthuthukiseni ukusebenza ngendlela efanele kwenqandamagciwane ezilwa ne-sepsisi enamagciwane kanye nokubhekana nokuphikisana kwezinto ezilwisana namamaykhrobhu. Imininingo etholakala kulolu cwaningo igcine ngokuthi kukhishwe i-athikhili eyodwa ebuyekezayo okokuqala, imibhalo yocwaningo emibili ebhalwe okokuqala, kanye ne-athikhili eyodwa ebhalwe ngokuhlanganyela ebuyekezayo.