Sains Malaysiana 55(4)(2026): 679-688

http://doi.org/10.17576/jsm-2026-5504-08

 

Ex Vivo Human Aortic Punch Tissue: A New Approach for Investigating Angiogenesis for Cardiovascular Diseases

(Tisu Pukulan Aorta Manusia Ex Vivo: Pendekatan Baharu untuk Mengkaji Angiogenesis untuk Penyakit Kardiovaskular)

 

MAISARAH MD RAZMI¹, AZIZAH UGUSMAN^2,4, NADIAH SULAIMAN^3,4, SAFA ABDUL-GHANI⁵, MUHAMMAD ISHAMUDDIN ISMAIL⁶ & NUR NAJMI MOHAMAD ANUAR^1,*

 

¹Programme of Biomedical Science, Centre for Toxicology & Health Risk Studies, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia

²Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia, 56000 Kuala Lumpur, Malaysia

³Centre for Tissue Engineering & Regenerative Medicine, Hospital Canselor Tuanku Muhriz, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, Cheras, 56000 Kuala Lumpur, Malaysia

⁴Cardiovascular and Pulmonary Research Group (CardioResp), Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

⁵Pharmacology Department, Faculty of Medicine, Al-Quds University, Jerusalem, Palestine

⁶Department of Surgery, Heart and Lung Centre, Hospital Canselor Tuanku Muhriz, Universiti Kebangsaan Malaysia, Cheras, 56000 Kuala Lumpur, Malaysia

 

Received: 29 October 2025/Accepted: 30 March 2026

 

Abstract

Cardiovascular diseases (CVDs) remain the leading cause of mortality worldwide, with pathological angiogenesis contributing to disease progression. Conventional ex vivo angiogenesis assays often employ animal tissues, but physiological differences limit translational relevance. This study establishes a human ex vivo angiogenesis model using discarded aortic punch tissues from coronary artery bypass graft (CABG) surgeries, providing a clinically relevant platform for investigating angiogenic mechanisms. Two culture approaches of embedded and sandwich techniques were optimized using aortic punch tissues maintained in Matrigel for up to 27 days. Angiogenic sprouting was assessed microscopically, quantified with ImageJ, and analysed using repeated measure ANOVA with Bonferroni post hoc test. No sprouting was observed with the embedded method. In contrast, the sandwich method induced vessel sprouting, initiating at Day 7 with progressive increases in sprouting area and branching length through Day 27 (p < 0.01). Under hypoxic conditions (1% O₂), sprouting was significantly enhanced compared to normoxia (20% O₂), with greater sprouting area, branch number, and branching length. Hypoxia also elevated HIF-1α expression, particularly at Day 7 and peaked at Day 14 (p < 0.05) compare to normoxia, confirming hypoxia-driven angiogenic pathways. The sandwich culture method effectively supports angiogenesis in human aortic punch tissues, unlike the embedded approach. Hypoxia further amplifies angiogenic responses via HIF-1α signalling. This optimized human ex vivo assay offers a clinically relevant model bridging in vitro and animal-based systems, serving as a valuable tool for mechanistic studies and therapeutic exploration in cardiovascular disease.

Keywords: Angiogenesis; aortic ring assay; ex vivo; human aortic tissue

 

Abstrak

Penyakit kardiovaskular (CVD) kekal sebagai punca utama kematian di seluruh dunia, dengan angiogenesis patologi menyumbang kepada perkembangan penyakit tersebut. Ujian angiogenesis ex vivo konvensional lazimnya menggunakan tisu haiwan, namun perbezaan fisiologi antara spesies mengehadkan kerelevanan translasi. Kajian ini membangunkan satu model angiogenesis ex vivo manusia menggunakan tisu tebukan aorta yang tidak digunakan daripada pembedahan cantuman pintasan arteri koronari (CABG), yang menyediakan platform klinikal relevan untuk penyelidikan mekanisme angiogenik. Dua pendekatan kultur, iaitu teknik terbenam dan tertindih telah dioptimumkan menggunakan tisu tebukan aorta yang dikekalkan dalam Matrigel sehingga 27 hari. Percambahan angiogenik dinilai secara mikroskopik dianalisis secara kuantitatif menggunakan perisian ImageJ dan seterusnya dianalisis menggunakanANOVA ukuran berulang dengan ujian post hoc Bonferroni. Tiada percambahan diperhatikan melalui kaedah terbenam. Sebaliknya, kaedah tertindih berjaya mendorong percambahan salur darah yang bermula pada hari ke-7 dengan peningkatan berterusan dalam keluasan percambahan dan panjang percabangan sehingga hari ke-27 (p < 0.01). Dalam keadaan hipoksia (1% O₂), percambahan didapati meningkat dengan ketara berbanding keadaan normoksia (20% O₂) dengan peningkatan keluasan percambahan, bilangan cabang, serta panjang percabangan. Hipoksia juga meningkatkan pengekspresan HIF-1α, khususnya pada hari ke-7 dan maksimum pada hari ke-14 (p < 0.05) berbanding dengan normoxia, sekali gus mengesahkan pengaktifan laluan angiogenik yang dipacu oleh hipoksia. Kaedah kultur tertindih terbukti berkesan dalam menyokong angiogenesis dalam tisu tebukan aorta manusia, tidak seperti kaedah terbenam. Keadaan hipoksia seterusnya memperkuat tindak balas angiogenik melalui pengisyaratan HIF-1α. Ujian ex vivo manusia yang dioptimumkan ini menawarkan model yang relevan dari segi klinikal, berfungsi sebagai jambatan antara sistem in vitro dan berasaskan haiwan, serta menjadi alat penting untuk kajian mekanisme dan penerokaan terapeutik dalam penyakit kardiovaskular.

Kata kunci: Angiogenesis; ex vivo; tisu aorta manusia; ujian cincin aorta

 

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*Corresponding author; email: nurnajmi@ukm.edu.my